No announcement yet.

Vorshlag Track BMW E46 Development Thread

  • Filter
  • Time
  • Show
Clear All
new posts

  • Fair!
    started a topic Vorshlag Track BMW E46 Development Thread

    Vorshlag Track BMW E46 Development Thread

    Project Introduction August 31st, 2015: This forum build thread originally covered the repairs and track prep on my wife Amy's 2002 BMW E46 coupe, which we purchased August 20, 2015. This car will get track prep towards a NASA TT class (which I will discuss in more detail in a future post), but initially we will be doing some maintenance and repairs to get this car inspected and reliable, to let her "daily" in this little Bimmer. No, we're not just automatically sticking an LS1 V8 in the car (unless the engine is terminal, and maybe not even then). She wanted an inexpensive "cash car" to drive to work, and I wanted a car to test some new parts out with on track, so maybe this one will fit both needs.

    Later this thread kind of morphed into a catch-all for the a number of BMW E46 chassis track builds we tackled... a red 330 coupe, silver 328i Sedan, and later an endurance road race car. I have altered the thread title in 2019 to reflect this more broad coverage, not just one specific car.

    The real question is: Can we make a daily driven BMW competitive regionally in NASA Time Trial?

    In this thread we will also cover some tips on "How to buy an E46" and also show the "Common Things that Break" on these cars and illustrate the fixes. If you ever wanted to own a BMW E46 this might be a useful read. I'm showing the basic costs and hours spent on this build as we go, since we log everything into MyShopAssist, the service logging and customer interface software we use on all tasks and all jobs here at Vorshlag.

    Cross-posting this to these forums:

    I'm posting this little build thread on a number of forums, and some of you will be chomping at the bit to talk trash or point out past mistakes on an E46 330 build I did back in 2009. Yes, I made some mistakes on that build and was very frustrated with the oil pump drive issues that this car suffered. No, I didn't listen to several people who warned me that what I was doing (revving the M54 engine too high, not welding the oil pump nut, etc) were going to cause problems. Some of you folks were right, I admit that, and I unwisely ignored freely given internet advice.

    Before you crap up this thread with old history and personal attacks, please read the next few posts - where I will address the oil pump issues, harmonic balancer problems that car had (that we didn't know about until much later), and give my updated advice on the M54 "minimum oil system prep" to folks, learned from these mistakes (in my 2nd round of posts). That 330 was built 6 years ago, in my home garage, and I have learned a lot since then. Vorshlag has gone through a lot of growth in that period, with a lot of new employees added to our staff, new capabilities added to our shop, dozens of car builds under out belts, and hundreds of cars worked on since then.

    As always, in this build thread I will share the good and the bad, as well as track all hours and dollars spent. I might make mistakes, but we will always try to learn from them. I will still admit that I don't know everything about the E46 chassis. We work on a variety of cars, and not just BMWs. I will specifically ask for help in this thread on a few areas where others know more. So again, please read the next few posts before you chime in with your advice - your comments might already be addressed fully. Thank you for your patience.


    This is a tough question to answer. First, let me talk about Amy - I'm damned lucky and have a wife who not only puts up with my racing addiction, but she's a racer herself. I met her at a race, so I guess that's how you do it. She's won 3 Solo Nationals Championships, is a licensed NASA Time Trial Competitor and race winner, and we both love to enjoy many forms of motorsports. We spend 25-30 weekends a year doing autocross, HPDE and TT, and I will get her in the W2W Endurance E46 next year with us, some how.

    These are two more E46 cars I've owned. The 323i sedan (left) was just a daily. The 330Ci coupe (right) became an autocross/track car

    She daily drove the red E46 4 door 323i (above) for about a year, but it was very stock and thus remained very boring. She decided in 2013 that she wanted a "big comfy BMW", so we looked for then found her a clean 2001 740iL. She really liked that 7, but we probably only had passengers in the back seat a half dozen times in 2 years of ownership. Its just the two of us most of the time in any given vehicle, so the gigantic-ness of the long wheelbase 7 series was a waste. Even though we did a lot of repairs, restoration and little upgrades to that 740 at our shop, we don't really make anything unique for the E38 chassis... so it was useless as a "business promotional tool" or test bed for Vorshlag.

    We just sold both of Amy's previous cars, the 740iL and the TT3 Mustang, and she gets this E46 as her replacement?!

    Why does she need a car? Well back in July we sold Amy's 2011 Mustang GT, which she and I raced in NASA TT3 and other classes the past five years. That car was her daily driver from 2010 until 2013, when we got the 2001 BMW 740iL (2013-15) for her to drive back and forth to work. We also sold that E38 a few weeks ago, and had a few bucks left from that sale to spend on her next daily driver.

    But one thing kept nagging me: We have been sharing race cars for years, she and I, and if I've learned one thing about that, it is that sharing a race car sucks. You get half the seat time at a track weekend, or you end up putting twice the laps on a car during a given day (running in 2 different run groups), which is very hard on the car. It never gets a chance to cool off or any down time to make tuning changes or repairs without being rushed. Amy and I shared the TT3 Mustang and then we built the TTC Corvette (1992 LT1 Corvette, Project #DangerZone) early in 2015, and we finally had them both at the track... for one NASA weekend this year. But it was nice, since we didn't have to share!

    Separate but equal: having his and hers race cars is ideal, so we don't double-up on a single car on a race weekend!

    So when it was time to move the 7 series on down the road we discussed a half dozen options for her next daily driver, which I was hoping to ALSO use for some new parts development and rack up some more racing wins for Vorshlag. Every car we own has to "do work" for Vorshlag, and having a daily driver that could at the very least test new parts was part of the deal. We looked for a clean E30, which would be "retro cool" after a lot of restoration and mods, but clean E30s are going for big $. Then we looked at E36s, but we have done that chassis many times in the past, and they are getting a bit long in the tooth.

    She said she wanted a BRZ or FR-S, and I worked up a wicked NASA TTC track build that she was on board with, until she saw the budget. No monthly financing payments was a requirement for this next car, and even used these are still $15-18K cars (oldest is 2013 model). It had to be a cheap cash car. We thought about Subarus (too kooky), Miatas (she daily drove one before - too slow, too small), even some domestics... but nothing had the bang-per-buck aspect of the E46 right now, at this moment.

    We had some money stashed away after selling the 740, so I looked for a clean 330 for $4-5K. Nope, they don't exist unless it has 200K+ miles and an automatic. Craigslist searching (yuck), AutoTrader (pretty much all dealers), and other sources. But being a small business owner, cash flow comes and goes, and one day "poof" the cash from the 740 was used for something for the biz - paying taxes, payroll, vendors - something. So my budget was slashed and the E46 choices at this new price range started to look pretty sketchy.

    This is our cheap, 197K mile 2002 325Ci project car. Yes, we know, the Foose wheels are Fooking ugly! They will be gone soon

    I put a call out on Facebook, and once again was rewarded with a diamond in the rough. A friend that worked at a used car dealer had a lead: 2002 325Ci, 5-speed, 197K miles, $1800. It needed more work than they wanted to invest, so they were willing to let it go cheap to someone who could fix it. Ding! Ding! Ding! We have a winner!

    This E46 we just bought is a bit rough around the edges (read below for description of problems) but since we bought it well I'm confident we can fix whatever is wrong with it. I test drove and checked the car out personally and couldn't see any frame damage, rust (Texas car all its life), it had a clear title, and it didn't run like it had a head gasket or oiling system problem (both potential "gotchas" on these cars). Everything else that could be wrong I'm not afraid to fix. Vorshlag has serviced 100's BMWs over the years and we are well versed in most of the problems and fixes of the E46, as well as performance upgrades that help these cars perform better on track and in autocross.

    whiskey dent: Dents or scratches on a vehicle due to drinking and driving or hitting an object with your vehicle while intoxicated.
    The car has a lot of "whiskey dents", small dings and bumps on the body that don't effect the function of the car, just make it a bit ugly (see the two pics above). It also had a light front end hit and another rear tap, but we will fix those issues as we go. Nothing that prevents it from being a good daily driver. The project name "Jack Daniels" comes from the Whiskey Dents, obviously. No, I don't condone drinking and driving - not hardly - but the name fits.

    These cars can get light quickly. This car lost 434 pounds in 2 hours (interior removal) and still has all the factory glass and steel!

    We like the E46 chassis, and have four of these in the shop right now. The silver E46 1999 328i 5-spd sedan above was purchased a few months back for an "employee owned shop endurance race car" project, and we already knocked a bunch of weight out of the car. This E46 328i was also well under $2K, also from a good Facebook friend lead, who had a tough-to-sell car, so it had some miles and needed some TLC. We can easily get weight out of one when we make it a real race car, as shown above. The door panels, carpets and seats on these cars are HEAVY! But this car needs to keep some of the interior, because its going to double-duty...


    "Do as I say, not as I do." Normally, I warn customers that taking their daily driver and making it ALSO work as their track car is a TERRIBLE idea. It always involves huge compromises that make it a less comfortable daily driver, a heavy/slow/less competitive race car, or both. But this is what SO many people want to do - I'd say half our customers do this! - so why don't we try this "dual purpose build" for once and document what works and what doesn't? Can we win a TT race, or even set a track record, in a REAL DEAL, full interior, air conditioned, daily driven street car? We did it with two BMWs before (below), but that was several years ago - when NASA Time Trial wasn't nearly as competitive as it is today.

    We took both the E46 330 and E36 M3 above to NASA TT wins and a track record each - when both were daily driven at the time

    This 2002 325Ci will be both Amy's daily driver (she has a mild 8 mile commute, all on secondary roads with lots of stop lights) and we will use will try to make it a competitive NASA Time Trial build and let her go have some fun in TT. The goal is to make it reliable and fast, allowing her to have as much seat time as possible. We're already building a new "shop car" E46 V8 for me for 2016 (TT1), plus the Endurance car E46 for the shop employees (1999 328i for WRL), and this E46 (TTE or TTD?), so we will have three shop E46 race cars in 2016, if everything goes to plan (when does it ever?!).

    Due to other expenses in owning a growing business, and two other race cars already designated as "shop cars", this 325 is being built on a very small budget. Not "$2000 total" like the GRM E30 we built before, but more like the TTC '92 Corvette we ran this year and has it's own Forum Build Thread. I've had customers and even people in the motorsports industry remark that those two "budget builds" (GRM E30 + Dangerzone) were some of the favorite we've done, more so than our more wild builds, so who knows? Those of you who dig that sort of thing might enjoy the build-up.

    continued below
    Last edited by Fair!; 07-27-2019, 04:40 PM.

  • Fair!
    continued from above


    There are always brackets needed for the outside window net, which needed to be added before the interior was painted. The owner at Safecraft is a racing friend of Tim's, and we sell their products. They donated a set of 6-point harnesses and three nets for our build - both left hand nets (driver's head net and window net) and a center net.

    The first one to get a mounting bracket was the outside head net - which looks triangular like the center net, except that it has this very distinctive quick release(see above right and below). We will add the center net after paint - it doesn't need anything welded to the cage to attach.

    "The Safecraft racing net features the easiest to operate release buckle we have used. The pin is easy to insert into the tapered buckle. The outward facing red release button is easy for rescue personnel to identify and operate, and the inward facing release strap can easily be pulled even with gloves on. Because the pin is round, you don't have to worry about removing any twists in the net before buckling it. This buckle makes for quick driver changes, and is the most fumble free available.

    Zach fired up SolidWorks and designed this bracket above, based on measurements he took. This was then CNC plasma cut, cleaned up and bent. The extra holes will hold the secondary fire pull and kill switch.

    The very distinctive Safecraft quick release mounting cup has a threaded shaft that was welded to these stand-offs, as shown above.

    Then this bracket Zach made was welded between our cage's A-pillar and FIA vertical bars. This makes for a solid mounting for the driver's head net Quick Release - which can be reached from the driver inside the car (via the red Nylon pull) or outside (the big red button). Once you use these quick release pins from Safecraft you don't ever want to mess with anything else.

    The separate outer mesh net is the "window net", which is what FIA wants to see - to keep debris out of the car. Having two nets seems overkill, but this is what ALL pro teams do on "windows down" cars like this. This Safecraft net is held in with an upper bar that has a spring loaded bracket (both brackets are welded to the cage) and straps to wrap around the door bars from below.


    Last but not least was the nasty job of cleaning up the sheet metal and cage tubes before the car went to have the inside painted. Everyone pitched in for this nasty job.

    Every bit of sound deadening that was left had to be scraped / wire wheel removed. The "crud buster" tool above was used quite a bit, as was a lot of Scotch-Brite red pads - and the entire cage was cleaned up of any residual rust or weld spatter.

    I cannot emphasize enough how much this job sucked - it just spit a lot of crud onto anyone involved, and even wearing full face masks and breathing filters, you got filthy everywhere else. But the more we cleaned, the less the paint shop would have to, and the better the paint job we would get for the money.

    On March 26th we had wrapped up all welding and clean-up work on the interior, and rolled the car outside for the first time in over a year. We had the ride heights mostly set, the big wheels and tires installed, the caged wrapped up, the doors and trunk off, and the windows removed - and it still looked pretty mean.

    The next day (a Saturday) I loaded the car into the enclosed trailer and took it to our painter, so they could get started on the interior paint work.


    We took the E46 to our preferred painter, Shiloh, at Heritage Collision up in Sherman, TX. Shiloh and his crew have painted dozens of cars for us and our customers, and he is the "go to guy" in Dallas/Ft. Worth for racers who need body and paint work. He also does show quality level paint, insurance work, the whole gamut.

    Shiloh helped me unload and we brought the car into his shop, where we were greeted by the two new shop kittens. We had spoken a couple of weeks before about the hard PPG interior paint he wanted to use and I asked him to order a color that was "red AF". And that he did! We are still up in the air about the exterior color, it could be this same shade of red or white or black. We shall see....

    Shiloh and his guys cleaned and prepped the sheet metal and cage even better than we did - I was embarrassed by how much better they made the inside look. But they take every job seriously and it results in a better finish.

    They taped off the exterior but painted the complete trunk area, and sprayed 4 coats of this hardened urethane - which wears very well on cages.

    Shiloh is great about sending progress pictures throughout the build, and there were no surprises when we picked up the car at all.

    I picked up the car on April 7th and was blown away at how good the paint work looked when the car was rolled outside. It was bright, shiny, Red AF and made this $100 chassis look like it was worth at least three times that much! The shop kittens were helpful when inspecting the work.

    We got the car back to the shop and brought it back inside... then it sat for several weeks while "life got in the way".


    We all got busy in May and skipped a few weeks of our Thursday work nights. Zach was autocrossing a lot, Tim was doing Pro race support, Myles had a new baby, and the rest of us had tons of other stuff going on. But Zach got back to the work first and tackled this task in early June.

    I really want our endurance car to have at least the shell of the OEM dash, and while this is something some team members disagreed with me on, so far I'm winning this battle. The example above shows a one-piece aftermarket plastic dash skin in another BMW race car. Our E46 will not look quite that clean - but this is about how I want our car to look.

    We kept the original dash from this car (very gutted and much lighter), and in previous entries on this forum I've shown what we did to make it fit. That has been out for a bit while we worked on the cage but it still fits. We also want to run a motorsports style heater box/defroster. We've used the box (above right) on many builds and it is both cost effective and lightweight.

    Why run a defroster? Well we do have events here in Texas in cold months. The January 2016 NASA event (above left) in my C4 - which had no heater - was a nightmare of a frozen windshield and foggy forward vision until the sun came out and thawed us all out. For about 8 pounds we can have a proper heater box, which we always point at the windshield.

    Instead of making the ducting manually, we kept the stock defrost ducting on the BMW dash. There is a junction in the plastic manifold that had a flat but funky shape...

    Zach made the two parts above. One can act as a block off plate and the other has an adapter for the 3" hoses that matches the defrost box outlet tubes. We will plumb one of the two outlets to the dash here and another to the center vent - to only use on very cold track days. It will keep the windshield fog free and - with the center vent opened - can put some heat into the cabin for times when you might be sitting in paddock or taking slow laps before the green flag drops.


    We plan to add a functional diffuser to this car, and as part of that plan we ditched the spare tire well and deep battery box in the trunk already.

    After the car came back from paint, Zach worked one night and built this aluminum flange that will hold the flat trunk floor panel. That panel was measured, added to CAD, and CNC plasma cut from some steel sheet. We used steel there to add rigidity, and to be able to weld to later. We will likely add a diff cooler, fans, and some other things to this panel. It will be painted after our first track test.

    Zach also designed and plasma cut two other panels. They both cover up the "vent holes" in the trunk, which are used to expel air pressure from the cabin when you close the doors with the windows up. Well our cabin will never have door windows, so those got covers. The second panel also serves as the new battery tray, higher mounted than the deep OEM piece.

    The image above shows the steel trunk panel set into place and the two side vent block off panels + battery tray riveted in place. Look for more action back here in future entries. The pic above right is from another E46 we built where we did the same thing - made a battery shelf because of a huge diffuser underneath.


    PowerTune Digital is out of Australia and they make this 7" LCD digital dash display for $500, which has CAN support for dozens of ECUs, including many OEMs. The screens are completely configurable, they have an optional GPS antenna, and we wanted to check them out.

    They just released Holley CAN support and we are testing the first one on an actual Holley EFI car now in our shop, on another customer's endurance LS powered Holley Terminator X-Max equipped car...

    This Cadillac was begun much later than our E46 but is getting done a lot faster - it is a customer build, so it gets priority shop work during business hours. We're just building our E46 a few hours over one night per week.

    Anyway, we made the image above to show the various AiM and Holley digital dash unit sizes, and the 7" PTD unit is as big as the large AiM but is $2100 less. It is going into this CTS-V and also my wife's narrow body C6 Corvette for testing. If we like how it works we will put one in the E46 here, too!


    We have a lot of parts on hand to add to the E46, like this coolant reservoir, oil catch can and accumulator from MasterLube. Getting all of these items mounted will let us plumb the oil, coolant and fuel systems on the car.

    We also installed this ICT Billet power steering delete kit, which will be run with a different routing than what I mentioned in the February post.

    There are hood latches to add, seats to mount, harnesses to install, and wiring to tackle. All work we have done before, just need to get it going.

    Until next time, thanks for reading!

    Leave a comment:

  • Fair!
    Project update for June 29, 2021: It has been a few months since my last post here and we have some solid progress to share this time. No, it still isn't on track yet, but we do have a finished cage, window nets, steering column, painted interior, and the engine bay is much further along - and we've begun plumbing work.

    We have been very busy with an onslaught of orders so I am more behind forum build thread updates than we are on actual project work. We have added a full time welder to our team to handle production fab work, which frees up Zach to do more car specific build work. Zach has been putting in the most hours on the Team Car this year, making up for a late start on the team. He's also a former Formula SAE builder and active autocrosser, so we have us another driver, too.


    In early March I stole Brad away from customer car work for a few hours to tackle the side quarter window install during shop hours, since he always does such a clean job of these Lexan installs.

    Last November we made a huge Lexan purchase for 5 cars, and about half of that worked out well. To save $$ on the Team Car we bought some slightly curved blank sheets, then in March Brad made a template in cardboard from another E46 coupe's Lexan windows and then transferred it to this blank sheet. He carefully cut both rear windows out...

    With a number of M4 rivnuts added to the frame of the rear side window opening he transferred the holes to the Lexan, then tackled the outer window trim that runs from the front to the back on an E46 coupe. It needed some clean up and paint, so it will be this satin black when installed after paint.

    Brad then countersunk the holes in that for the Tinnerman washers and countersunk M4 stainless bolts. since our blank sheets weren't long enough, we decided to cut the windows a bit short and sink the glass flush with the metal B-pillar, shown above right. I had wanted the leading edge of the quarter glass to extend forward then curve inboard for some drag reduction, like on the '69 Camaro below.

    On that car I bought some Lexan that was .093" thick from a local store and Zach and Brad built custom quarter windows with that inboard tilting leading edge. Zach experimented with several bending techniques and settled on just putting it in the sheet metal box and pan brake, then giving it a light bend - which stayed. We will take some small scraps of this thinner Lexan and make the leading edge bends for the E46 coupe in the future.

    Last but not least, Brad peeled back the protective film and marked off a 1" border. This was scuffed and painted black, as shown. This helps hide the ugly sheet metal underneath the edge of the Lexan. These windows won't be reinstalled until right before the track test.


    As I mentioned in our last installment, we were looking at this K&N RP-5135 filter to use for an OTR routing. Making it fit under the radiator support was going to be tricky... we were building this car to use a 90mm throttle body

    Myles and Zach mocked this up and it looked massive and perfect - just needed to order some hose to get to the final location.... that silicone hose with a 15 deg bend arrived a couple of weeks later and then the guys trimmed up the back side of the upper portion of the radiator support to try to make this massive air filter fit.

    I had my heart set on a "ram air" setup with a sealed airbox behind the filter, but after several cardboard mock-ups (see above) it was looking very constraining to both the filter and proposed hose routing to the radiator. Without an all new radiator placement or a completely different filter shape, this wasn't going to work. We already had too much time in this rolled radiator mount and I wasn't about to contemplate starting over - just for some mythical "ram air" that isn't even shown to be quantifiably better than "non-ram air" intake setups.

    So Zach proposed cutting the radiator support upper section off. I wasn't having it - that could ruin the whole front end structure, hood mounting, etc. "How much did this radiator support cost?" Well, yea it was only $50. So sure - cut away! Worst case we just buy another. Lo and behold - even with the entire center "bridge" cut away the structure was still very rigid. I was wrong on that, thankfully, and we all felt good keeping this modified radiator support as the basis for our hood latch pins.

    Once that was trimmed it opened up all sorts of possibilities! We could then slide the filter forward of the radiator (which was confined by the upper support and length of hose we had with that 15 deg bend). I ordered another 3.5" piece of hose, then a Vibrant coupler. I will show the rest in another section below.


    With the upper radiator support cut away it was time for Tim to step in and sort out the radiator hoses. This can be tricky as it is rare that you get to keep the same diameter at both ends of a given hose, and we often have to use "adapter" hoses that we splice together.

    We used this rotating thermostat housing at the water pump that lets us "clock" the outlet within a range of angles. Tim has laid out the hoses on a number of builds and knows a few brands to go to for the bends and couplers.

    This is the final result of the upper and lower radiator hoses, which match the Griffin radiator we ordered and the LS outlets. Clean routing, nothing crazy. When the air deflector (see that task below) went back on with the hoses in place, there was a slight tweak to clear them, which we will clean up further in a later task.


    We finalized the Prius steering column location and mounted it with the Keyser bracket to the dash bar last time, but we all felt it needed a "bit more" stability.

    Myles tackled this task - he took a bent bracket that came with the Prius column, then added some tubing to connect that to the BMW's steering column mount bracket.

    Kind of a funky shape but it all fits perfectly, and with the assembly fully TIG welded the column has proper support for the heavy motor hanging off the side of the electric assist column. Now that the top of the column was located properly we could focus on the firewall mount and then build the steering shaft. Some of the work below happened after the interior paint...

    We worked through several ways to secure the steering shaft at the firewall - as we had removed the OEM support there, due to our non-BMW steering column. Like we have done on many custom steering shaft solutions, we utilized a common race car flange kit that sandwiches a spherical bearing. Then Myles CNC plasma-cut an adapter plate (above at left) that was welded to the large opening in the firewall. The 2-piece flange kit now bolts to that and the 3/4" DD shaft passes through this spherical for proper support.

    The steering shaft is a simple design using parts we developed in 2006 - but unlike most of our 2-piece steering shafts, we had to weld the U-joint to the upper 3/4" DD shaft section. Why? The set screws were in a weird place, since this was such a custom application. So Myles TIG welded that junction. Everything else is bolted together with the set screws (with drilled detents on the shafts and red Loctite holding it all together.)

    With a 2-piece 3/4" to 1" DD collapsible shaft assembly and our BMW 54 spline lower U-joint. You can see where we had each shaft size section in the picture above left. The above right pic was after the interior was painted and shows where the spherical shaft bushing mounts to the welded plate on the firewall.


    The new placement of the large K&N filter and subsequent removal of the radiator support's upper bridge removed a good place to hang a "cold air" box from, but also allows more airflow to and around the air filter.

    To guide the path of incoming air from the upper grill openings (in the hood) we decided to build an air deflector. This would separate the air from the upper grill (which will feed the air cleaner) and the lower grill (which will feed the radiators).

    Zach made a cardboard template then transferred this to aluminum sheet. The plan was to incorporate mounting into the existing upper radiator mounts, seal off to the front bumper cover and mount to the bumper beam as well.

    There are still some small details to complete but this should wrap up most of the work that went into the air intake, air filter, and air deflector. Excess air that gets past the filter is aimed at the the top of the engine bay, and should be pulled out of the large vents in the carbon Seibon hood.

    While working on this air deflector Zach also built some additional bumper cover brackets, shown below. This was something I asked the crew to tackle, as we only had a few points of contact with the bumper cover to the chassis.


    This was the only pre-cut piece of Lexan we got in the large 5 car order that was utilized on this E46. Luckily this one fit well.

    Once again I asked Brad to tackle this - and he pre-drilled the holes in the Lexan and added the mating rivnuts to the chassis.

    More stainless M4 countersunk bolts and Tinnerman washers spread the load on the hardware to keep the Lexan from cracking. The window is mounted well enough that it should not need any support bows in the back window - but if our first track test shows some flutter on the back window we can cut and bend up some aluminum supports to span the vertical opening of the back window.


    This was a last push of work nights to get the cage 100% wrapped up, then to add some cage-to-chassis plates, remove the last bits of metal inside we don't need, add window nets and mounts, as well as a panel to house the external fire bottle pull and battery kill. The goal was to get the car to the painter before the end of March, which we did.

    Over several Team Car work nights Zach and Myles knocked out the final welding work, added a few small tubes, then finish welded the rear shock tower reinforcement plates.

    Towards the end of this work I knew we were still missing something that we tend to add to all cages....


    That's what it was, these chassis tie-in plates. We made some simple steel plates that tied the cage to the A- and B-pillars, and of course added dimple dies.

    Since I knew someone would ask, yes - these are legal for the classes we plan to run this car in. And also yes, we weighed them.

    These were stitch welded to the A- and B-pillar as shown above and while they add some extra rigidity to the chassis, they add almost nothing to the weight. We're already going to have to add a LOT of ballast to run even close to 300 whp in WRL GTO class.


    While this welding work was going on the guys chased a few more pounds by removing some unnecessary sheet metal structures inside.

    Little seat belt brackets, rear package shelf structure we hadn't chopped away fully, and the battery box. The rear spare tire well was already removed by Tim previously.

    This wasn't done so much for weight savings as clean-up of some quickly cut away parts, and to get us that much closer to being able to paint the interior and not regret leaving things unfinished.

    continued below

    Leave a comment:

  • Fair!
    continued from above

    The guys made a tracing of the inner sheet metal portions of the rear shock towers - which are NOT symmetrical - and made these CNC cut "windowed" reinforcement plates, then bent them to match. There were also top plates (also not symmetrical) that were cut out and the inner edges "curved" to match a fillet in the sheet metal. This is made to "box" the shock tower reinforcement and give some impact strength to the top of the towers, where they usually fail.

    Zach cleaned the towers and MIG welded these along the edges plus some rosette welds in the holes added to the structure. We have some clean up work to do but they are pretty beefy. I will show more of this in the next update once it is cleaned up, primed, and ready.


    A number of things that we chopped up needed some aluminum panels to replace them, like the trunk floor - that was an easy template, but we're going to wait and cut that until we have mounted the remote fuel surge tank + both the diff and trans coolers and pumps.

    We also want to make a raised "false floor" for the driver's side. As you remove carpet bits the floor becomes very "not level", as shown above right. The left side drops down nearly 2 inches, and there's a rib in the middle of the pedals. The foam insulation under the carpet is 4+ inches thick in these areas to make this "flat", but carpet is long gone in this one. And driving a car with a funky floor is distracting - we always try to remove distractions to the driver!

    A "false floor" covers up all of the uneven floorpan issues with a rigid, drop-in section of aluminum that normally incorporates a "dead pedal" on the left side. We have made these for a number of cars but never an E46 with the stock pedals, so this might be something we want to replicate and possibly sell some day, so some extra thought went into the template.

    After I spent some time showing Zach what I wanted in this false floor panel panel he whipped up this template with integrated mounting tabs along the perimeter. I feel we might need a reinforcing rib or stand-offs along the centerline, but we'll make these adjustments to the prototype when we cut this out. Next time we should have the first iteration cut, bent, and in the car.


    The Prius steering column mount has changed a couple of times on this build already, but it was always a kludge. I kept trying to push the idea of a "kit" that we could sell for an easy EPAS upgrade - any development work we could push to a product solution was a win. We were also debating keeping the E46 dash bar, but already had to cut it to get the down tubes in place, but tacked the rusty tube back together for the time being. Then we added the real dash bar for the cage so we had TWO dash bars. This is less than ideal...

    We kept parts of the OEM dash bar because I really wanted to keep the Prius' tilt mechanism and make the column a bolt-on affair. Without a bunch of diagrams, videos, or more words - this is just not possible with just a "bracket", and this frustrated all of us.

    The tilt wouldn't work and the angle of the column was all wrong, not to mention it had a lateral offset. So we punted on the "bolt on" idea and ordered a real dash tube column mount.

    After looking at a lot of brands and options (many of which were out of stock due to the pandemic), in mid-January Tim found this Keyser billet aluminum adjustable column mount. It was the closest thing to the diameter of the Prius column - with a little machining on the lathe it fit perfectly.

    In late January, Tim, Magan and Myles got this assembly in the car and we started "Test sitting" the full range of heights of drivers, from Tim to Magan. This will not be adjustable "on the fly" like the OEM Prius column adjuster could have been, but they found a height that fit all of the drivers. This will allow us to cut away much of the OEM dash bar, but some of the structure will stay to hold the skinned dash cover.

    This was also when we determined that the 320mm steering wheel was too small and found a 350mm wheel that better suited our needs for endurance racing. Slow the hands down for more control, less twitchy. There is one more small bracket that will be added to the column, to support the front end, then we can call this task complete. And more importantly, we can move onto the firewall bearing mount, build that last piece of the steering shaft, and wrap up the steering system once and for all.


    There are many ways to get filtered air to a V8 engine with the throttle body at the front. This is often compromised by the radiator being close to the engine so we often make a 90 degree turn and put the air filter in an area sealed away from the engine compartment, where it can get "cold air" instead feeding the engine hot air from the radiator exhaust. This tubing, filter and air filter housing combined are often called the "Cold Air Intake", or "cold air" for short.

    I am a big proponent of running the biggest filer element you can fit, and there are calculations and flow rates for any given filter. You also need to watch the tubing size and run as large or larger than the throttle body you have. We found out the hard way that running a 1/2" smaller tubing size than the TB can eat a big chunk of power - 15-25 whp can be choked off on a mild LS engine (we had to re-make the cold air intake on the FR-S above and found nearly 20 whp).

    The 90 degree bend also costs power and the engine bay can limit the size of the filter element, which can limit airflow. Getting the cold air tubing "Over The Radiator" (OTR) can give you a BIG area ahead of the radiator to stick a giant air filter - like we did on "Big Red", our 2011 Mustang we ran for 5 seasons. But there was still a 90 deg bend that was even compressed a bit to clear the (modified) under hood structure.

    With our rolled and lowered radiator mount we can still sneak a 4.5" silicone hose between the bottom of the upper radiator support and the coolers, and the whole cold intake tract is only 10" long and has one 30 deg bend. This massive C6 Corvette replacement K&N filter fits entirely in front of the radiator support and is still well behind the hood's upper grills.

    I ordered the silicone hoses weeks ago but all of our shipments have been delayed due to the crazy winter storm last week. I will show the installed silicone tubing and filter mounting bracket next time, but just mocking this up made me extremely happy.


    We have covered 8 months of work this time - and remember, it was almost all done a couple of hours one night every week. But the punch list is still large. The entire fuel systems needs to be built, as well as the exhaust (which we have parts on hand for). The false floor needs to be completed, as does the steering column/shaft.

    Once the steering and some chassis wiring is done we can put the dash pad back in, then we have to order the digital dash display, finish the switch panel that Magan made and add switches and dials. Then install the Holley EFI system. Make all of the coolant lines, lots of oil lines, diff and trans coolers, flares cut to fit and installed, lower side skirts installed (parts here), side mirrors chosen and installed (you don't want to know how long I've looked for good options there!), and more.

    Given my propensity to post memes, Zach printed out this one (above right) with a target date for the car to move under its own power - April 10, 2021 - which is 24 months to the day after we started this build. Let's push push push to make this goal!

    Thanks for reading!

    Leave a comment:

  • Fair!
    continued from above


    The E46 cage kit we bought from Hanksville has been tweaked, changed, fitted, added to, and welded in place. All of the work has been after hours and it is 90% done. Normally a cage takes a couple of weeks, but doing it in 2 hour bursts once a week definitely drags things out, and it is easy to lose where you were the week before.

    ​ ​

    Myles has done most of the welding on the cage on work nights when he could make it, which were a bit scarce for a bit with a new baby at home. But the main cage parts are completed and both door bar sections were in place. The kit originally had an "X" on the passenger door but we changed that to the ladder style NASCAR tubing. As you can see in the pic above left, we are extending the verticals downward to the stock rocker structure - with load spreader pads. This makes the cage door structure REALLY strong, and more than makes up for any small weakness added with the "S" curve.

    Our newest fabricator / technician / engineer is Zach (above right), who worked with Myles in FSAE years earlier. He joined us in November of last year. He has been here for all team car work nights since and has helped with some of the cage tube fitting and TIG welding. We added the FIA vertical tubes to the kit (see above left), like we always do.

    Zach has jumped in with both feet on the team car, to both show his fab skills as well as to get a spot on the team - so he can drive this car! He has fitted the optional FIA bars and started on the optional roof bars.

    Zach and Myles worked on the roof bar and the main hoop diagonal. Next was the upgrade from single foot protection bars to the triangular tubes we wanted...

    Zach made this structure above on the fab bench to be able to cut / cop / TIG weld these tubes together. This trick allowed him to weld the junction and "foot" to the end of the triangle, then he only had to stand on his head to weld the two legs to the main down bar and the foot to the floor.

    Smaller diameter tubing was also cut and coped for some triangulation at the top of the cage. These also work REALLY well as a grab handle when getting into and out of the car.

    We are close to wrapping up this task, and I will show more of the cage work as the last few tubes are welded in.


    Cooling for an endurance car is not something you can minimize. When we began working on this car we had a leftover Mishimoto drop-in unit we could have used, but that is setup for BMW's stupid "quick connect" radiator hoses - which are a huge PITA. Instead, we wanted to use a bigger, custom sized, rolled radiator on this endurance car. This could gain some room for an air filter over the top of the radiator. So when it came time to buy a radiator support (this car had none - see last time) we cut away the center bits to make room for the roll. We also designed the curved, tubular bumper beam to push as far forward as possible, to give us the most room for the radiator.

    After taking some measurements, Jason and I dove into the catalogs of Howe and Griffin for a universal fit radiators that maximized our room. These are two U.S. brands that make aluminum radiators for circle track, and the costs are always low, but you have to spend a bit of fab time making mounts. We ended up buying this Griffin 1-25182-XS, which is an all Aluminum unit that is 22 inches wide, 19 inches tall, and 3 inches thick. This is a "single pass" radiator with the upper inlet on the driver's side and the lower outlet on the passenger's side (which is why we went with the LS7 water pump config we described earlier).

    The Griffin radiator was made to order and took a few weeks to get here. It arrived by early June, and we wrapped the core in corrugated cardboard to keep the fins from getting smashed during construction. We didn't have the drivetrain back in the car until late June, and eventually started the radiator install in late September. The mockup began by sitting the bottom tanks on some jack stands and we tested several different angles. With the core support trimmed away laterally we could roll this core as far as we wanted.

    By late October we got back to this and Tim made some valid points about not having the leading edge of the radiator almost touching the bumper cover (a light impact would destroy the core and put us out of the race), so the angle of the roll was reduced from close to 45 down to the final 39.3 degrees. We also cut off the radiator fill neck, which would be plated over. The coolant fill would happen from a remote reservoir.

    Myles designed some upper radiator brackets in early November and cut them on the CNC plasma table. Zach was with us full time by then, and he machined the aluminum pins for the upper mounts to fit inside grommets for these brackets, plus capped off the old filler neck hole.

    Later in November the "ground plane" for any potential flat bottom body panels was checked, to make sure we hadn't dropped the radiator too low - it was still 1.5" above that, so we were good to go on the bottom mounts. Somewhere in this month the lower fiberglass headlight trim I ordered arrived, too.

    Now we are in December and Zach and Myles teamed up to make this lower radiator support. They CNC cut some flat 18 ga steel sheet, then bent it in the box brake, then added dimple dies to the lightening holes.

    The uprights welded to the lower part and two nutserts were added to the frame rail to mount it, as shown above. This let the radiator sit in the lower portion that is parallel with the angle of the roll. Two rubber bushings went into two of the holes with more aluminum pins welded into the end tanks for positive location and isolation.

    They painted the cradle black and the upper mounting brackets were bolted to the modified radiator support. Several inches separate the radiator core and the bumper beam + sheet metal bumper cover bracket, as shown above right. Four isolated pin mounts secure the rolled radiator and there's still room above it for an air filter, which I will show later.


    This coupe chassis was stripped of literally anything of value when we got it, so we had to go chase down a number of silly missing items like door handles, latches, and the like. Don't start with a complete rag of a chassis and you won't get bogged down in this little stuff like we did.

    We ordered an inner door latch for the driver's door, an outer door handle, and an inner door release from various sources. This is about the only thing eBay is good for in the car world - finding used OEM parts from junkyards.

    We kept enough of the door structure to attach the latch, and on the driver's side we kept the upper structure - as it helps during driver changes, in case somebody leans on the door. The passenger side is stripped of much of this upper / inner structure. Well it made it easy to add the inner latches, which were found on RockAuto.

    The carbon hood has no latches at the moment but we found the adjustable "hood bumpers" and ordered those, which thread into the upper radiator support. This helps cushion the closing of the hood and helps set the hood height.

    WEIGHT CHECK - OCT 2, 2020

    This "weight check" on October 2nd gives us some idea of where we are with respect to weight. Of course when I post these pics on social media, people lose their ever lovin' minds and "can't understand why you post incomplete weights!!!!" Goodness, people, just calm yourselves. Why did this clearly incomplete weight data hurt you? We post a lot of weights throughout every build, and of course we will post the final race weight when the time comes, too.

    This weight has the entire drivetrain and suspension in place and complete, 95% of the cage completed, the big front brakes, the EVO III seat, the 18x11" wheels, radiator, full sized Optima battery, and more. We have none of the glass in place (2-layer safety windshield and Lexan rear), the sunroof panel wasn't in yet, none of the auxiliary coolers, and no fluids. At worst we might gain 200 pounds? So we might need to add ballast, otherwise we will be really capped on power with WRL GTO's 9:1 pounds per whp limit (and that weight is without driver).


    In October we received our first E46 / TKX / 210mm diff driveshaft. This is a 3" diameter aluminum unit with a slip yoke at the front, which we can configure for T56, T56 Magnum, or now the TKX. The back can be configured for E46 non-M 188mm 4 bolt axle flange or the stronger 210mm E46 M3 axle's 6-bolt flange we have installed.

    Mounting this was completely straightforward and the 3.0" OD tube just cleared the factory center-bearing stamped sheet metal brackets in the tunnel. If it is too close there for your comfort, just trim away those stamped sheet metal mounts in the tunnel - they are no longer needed with this one-piece unit.

    One less thing on our punch list, and one more part to add to our E46 LS swap kit offerings.


    After months of waiting a large Lexan order came in from a new plastics / window supplier in November - who we will never use again. We ordered plastic for 5 different cars and they screwed up over half of the order - live and learn.

    We received the back window pre-cut but the side windows they didn't have patterns for (but never told us) so we just have some curved stock we will have to cut to fit. Will show more of this next time. Again, we will NOT be using a plastic front windshield, and instead will use 2-layer bonded safety glass windshield, for various reasons.


    Another mid-November task was removing the spare tire well. We do this on any build where we have plans for a diffuser, which we do on this car.

    The old stamped steel bits weighed 11.8 pounds, and will be replaced with some aluminum sheet metal, probably .080" thick. More on that later.


    After the protracted radiator mount task it was time to mount the only other front mounted heat exchanger on the list - the engine oil cooler. Remember, for WRL GTO we can only make around 275-330 whp, depending on our final weight, which should be easy for our 5.3L engine. But the 385" / 6.3L engine that is going in later it will make closer to 500 whp - so we are sizing all of the coolers for that power level (which we could run in AER events or NASA ST/TT classing).

    We had a leftover Setrab cooler (below left) we could have used for engine cooling, but we're going to overshoot all of our cooler sizes and engine oil is the most critical. So we'll save the smaller Setrab for a trans or diff cooler, and we popped for the largest "plate and fin" 10000 series Derale cooler for the engine oil (below right).

    At this point we knew we had to save room for the OTR air filter and hose, so Zach built this oil cooler mounting bracket setup for the Derale.

    There are 100 ways to mount an oil cooler and we went with s simple set of 1x1" aluminum channel, bolted to some aluminum angle that welds to the tanks. We got some pushback when I showed this on social media, but we always see the arm chair quarterbacks do this when we show details this closely. It will either work or it won't, and we should know during our first track test. This mounts on the front face of the radiator stack and covers about 1/2 of the total surface area. We have a thermostatic bypass for the oil cooler we will mount, of course, so we don't "over cool" the oil.

    This stacked set of heat exchangers will be fed entirely from the lower M3 grill opening, with sheet aluminum ducting forcing air through the coolers and not around them. If we need more airflow we can cut some holes in the bumper cover. The upper grill openings in the hood will be used for the air filter.


    Moving the rear springs from the stock "divorced" location (see below left) to a "coilover rear" location (our E46 endurance car, below right) moves the suspension loads for the suspension completely. Normally the shock tower only sees DAMPER loads, which is about 1/10th the actual SUSPENSION loads.

    This is why we rarely move the spring location to coilover rear, unless there is a very compelling reason to do so. The stock shock towers were NOT made for full suspension loads, and although a few people have done it without reinforcement, it doesn't take much time or abuse to blow out the shock tower. We've seen this happen too many times with just damper loads on street cars, and without coilovers, you just don't press your luck on this E46 chassis.

    We have made spherical rear shock mounts for a bunch of cars for a bunch of years, and we always design them for full SUSPENSION loads, because we cannot control what the end customer does with our mounts. We offer upper perches for our shock mounts, to make coilover conversion use possible. When we described what we wanted to do with this car to the guys at MCS they highly recommended a coilover rear and dual spring setup, so we went that route.

    There are a lot of folks who cage BMWs and believe you have to throw a dozen bars in the rear - to tie into the subframe mounts, to reinforce the shock towers, and more. They often end up with jungle gyms in the back seat - but we are not among the group that thinks this is necessary, and I am not getting into that argument here. After much internal debate on this subject, this (above) is what Zach and Myles came up with for our E46 with coilover rear damper and spring.

    continued below

    Leave a comment:

  • Fair!
    continued from above

    Here are some pics of the shifter hole that was opened up to fit the Tremec TKX shifter placement - admittedly they went a little too far forward on the cuts - this will all be covered by some aluminum sheet metal and hidden under a Joe's Racing shift boot. The second pic above shows this with the stock dash in place, and a shifter handle we mocked up. We will build and offer one to fit around the stock dash section here, which we plan to keep in place.


    We had a set of gold 17x10" Forgestar F14 wheels on this E46 coupe for the initial part of the build simply because they were on hand. I bought these as a second set for my red TTD/TT4 330Ci. When the buyer of that car picked up car, he chose only the silver 17x10s and decided not to buy these gold spares.

    These 17x10" wheels don't really fit the non-M E46 fenders, and we ran the HARD Motorsport flares above to clear the wider-than-usual "245" Hoosiers. We can't use Hoosiers in endurance racing, of course, and had always planned on a wider 18x11" wheel and much wider 315/30/18 200TW tire.

    We have been a dealer for Forgestar since 2012 and have sold many hundreds of sets of wheels. Many things have changed with this company, including ownership - multiple times. Weld bought Forgestar, then MOMO bought weld, and MW Wheels was the end result. We quickly realized they were no longer interested in making these custom offsets and patterns we needed - they added a heinously high "bespoke" wheel charge in 2020. When the 18x11" wheels we spec'd and ordered for our E46 arrived in late April 2020, and they had built them for the wrong bolt pattern, we were not shocked.

    It was easy to see before we had mounted tires, as we always "test fit" wheels to the chassis before we throw tires on. Not what we wanted to see, but "stuff happens". We re-ordered the 18x11's with the same PO but emphasizing the information on the original PO with the 5x120mm bolt BMW pattern. The 5x4.5" pattern they were built with accidentally fit another car in our shop, the '67 Mustang above left. So we got "lucky", other than losing months for the correct spec to be built.

    The correctly made wheels arrived in July, so we triple-checked everything. Then I took the wheels to mount up a set of 315/30/18 Rival-S tires. Always test fit custom wheels to your car before mounting tires! The used 315mm Rivals are from my wife's FR-S and will work for initial "driving around", dyno work, and first-fire testing. A fresh set of new 315mm tires will be installed before we attempt any laps on track, as these tires are pretty old now. What tires will we buy? Stick around and find out.

    We added a hair more room to the rear to be able to clear the coilover rear shock setup, so this is only a bit more "poke" you would see on a non-M E46 with 315mm tires on 18x11" wheels.

    We did some initial testing on the front and back, checking steering clearance at lock (it will need some trimming), and then got busy on other aspects. Will it need a flare? Of course, it will need BIG flares at both ends.


    A week later, mid-July 2020, we got to work trimming the fenders to fit these fat 315mm tires on the 18x11" wheels. It was clear (below) that we had some serious poke to cover up and I had purchased some Clinched universal "Euro" flares for initial test fitting.

    After removing a spring on the front strut, Tim and Magan took the front suspension to "full bump" and of course the 315mm tire was crashing into the fender lips long before the damper ran out of stroke. The 2" of tire poke would easily be covered up by the flares we had (above right), but they would require a considerable amount of trimming.

    Tim marked then hacked away the offending fender lips on the front using an air body saw and the "spinny wheel of death". These initial cuts look pretty nasty, but all of this is hidden under the flares and we will clean up the edges. But with this clearance the tires could go to full bump travel, where the tire would be running into the inner fender along an arc and not slicing into a sharp fender lip.

    The rear fender clearancing and cutting is a LOT more work than the front of any unibody car, and as such I had Evan do this one on the clock. He has flared a few cars while working here and knows all of my tricks, and then some. He marked the outer skin at the line where the inner fender starts to curve down and chopped that off..

    Then he cut the inner fender lip at the same height. This leaves an inner fender gap but the inner structure no longer curves down to meet the outer lip. He cleaned up these two sections of sheet metal for the next step - bridging the gap with some steel sheet.

    We keep 18 gauge carbon steel on hand for making these patch panels when flaring cars and Evan got to work cutting a strip about 3" wide that would arc around the curve of the fender opening and overlap both sections. He then tack welded these in place to the inner and outer sheet metal, which had been cleaned of paint and undercoating. The insides of these sheets still have stuff on them that cannot be cleaned, so this welding causes small fires on the interior. A person sitting inside the car with a squirt gun can shoot a little water at these flare ups and they go right out.

    Above you can see this 3" strip of steel sheet being tacked to the outer edges of the outer fender metal. These cover the gap and overlap the inner fender structure - to tie it all together. This stuff is a bear to weld due to the crap on the insides you cannot get off, so a series of skip welds are done. Tack, move an inch, tack, move an inch, and repeat until you have a fully welded seam. This adds the structure back to the unibody tub that you cut away and leaves a flat inner fender section for maximum suspension and tire clearance.

    With the stitch welding wrapped up the outer portion that protrudes past the outer fender skin is trimmed off and the weld is dressed with a flap wheel. The shots above show the inner fender patch panel after it was fully stitch welded, then seam sealer was applied, then zinc-based metal etching primer was applied inside and out. Leave any of this raw steel and it will rust, so get the inside too. The seam sealer makes it all water tight so nothing gets inside the cabin, too.

    Obviously this shot above still looks pretty crude but 90% of the heavy lifting has been done. Adding the actual flares is the easy part. Well, normally. These flares are "universal fit" and we want to add some extra venting on the back sides for less drag, so we will have to do a lot of fitting on those - which comes later.


    For a long time we had the stock Prius steering wheel in the car, but it was hideous and huge. In April 2020 we started measuring the splines and looking for a bolt-on adapter for use with a 6 bolt / 70mm PCD aftermarket steering wheel. After a lot of searching and some questions sent to Sparco we finally found the right hub adapter.

    By August 2020 the Prius steering hub finally arrived - yes, it 4 months it took to get from Sparco. Not a hugely popular car to prep, it seems. One thing we had settled on was the Lifeline/Sparco quick release hub, which we have on almost every single car in the shop. This was a sponsored part given to us one of Tim's race team owner buddies.

    We happened to have a Model 88 MOMO wheel in stock, which we took as a return from a customer - so one more "leftover" piece made it's way into this build, for now.

    ​This wheel is actually pretty small in diameter (320mm/12.5"), and that makes for a faster steering action - which is more suited for an autocross car. This Model 88 also comes in a 350 mm diameter, which is more suited to an endurance road race car.

    In January 2021 we had a new seat in place (after 2 additional seat changes - see below) and tested with 3 different size steering wheels from other cars in the shop with the same Lifeline/Sparco QR. The 350mm diameter is actually better suited for the new seat & steering column, and gives us both a slower steering response (good) and more visibility for the digital dash that is coming.


    Hang on because this is a bit of musical chairs. Back in April 2020 we had developed an early version of an E46 seat bracket base, then fitted this Sparco EVO III, which is a very wide seat. We did this to fit one or two big drivers on the crew, but they have since lost a LOT of weight, so I was wanting to fit something better. I had a customer who needed this EVO III and sold it, knowing we'd use something else from our inventory.

    By October 2020 it was time to look at a better, safer seat design. I had an extra OMP RS-PT "halo" style seat on hand from our old lobby seat displays and it was still within the FIA 5 year window, so we all "test sat" in that and got to work on a better seat install.

    Myles had also finished welding in the strengthening ribs on the prototype E46 seat base and we had it powder coated, so Tim and Magan worked on the slider and seat side bracket install for the OMP.

    Well that OMP was needed for yet another customer emergency, so we pulled it out and happened upon my all time favorite seat - the Sparco Circuit II. This is the wider version of the halo style Circuit seat, and it actually came out of my old red 330! In November while at the Optima World Championship Autocross (above right) at COTA, I traded an EVO II US for this Circuit II, and we got to work installing seat # 3 on the endurance E46!

    This went in with the same Sparco sliders, and yes, we will have to add a seat back brace for use with those in W2W racing. The sizes of our drivers is diverse, but we all fit in this seat. The Circuit II works well with long torsos for tall peeps like Tim and I, but also works on drivers that are more compact. Since this is my favorite seat I am going to hang onto this one and make sure we don't install seat #4!


    There are a number of options when it comes to factory Gen III and Gen IV LS serpentine belt and engine accessory arrangements we can choose. We tend to stick with two of the most compact options: the 1998-2002 "F-body" and the 2004-07 CTS-V/G8 setups. We decided to go CTS-V so in August 2020 we purchased Gen I CTS-V alternator and brackets for use with out E46 LS build. We like the compact fore-aft pulley placement of the C5/C6 Corvette and CTS-V/GTO/G8, and the C6 LS7 Corvette water pumps can work too.

    We chose the later (2009-13) Corvette C6 Z06 / LS7 water pump for our build here, as it puts the output port on the driver's side (see above left). Alternately we could have chosen the early C6 LS7 (2006-200 water pump (see below left), which has the pump outlet on the passenger's side of the engine bay. We pick one or the other depending on how we have the radiator inlet/outlet arranged.

    On this S550 Mustang LS swap above we are using a Howe double-pass radiator with its inlet and outlet both on the passenger side, so the upper hose can have a shorter run with the early C6 LS7 pump, as shown.

    Our E46 is using a "single pass" custom Griffin radiator with the top inlet on the radiator on the driver's side and the bottom outlet on the passenger side, so we chose the late LS7 water pump. We will show more of this in the radiator mounting section, below.

    The alternator is a 150 amp unit from a 2004-07 Cadillac CTS-V. We like this packaging the best - the CTS-V alternator is mounted tight and low to the block with a unique, extra mounting arm cast into the unit. This allows for another bolt to attach to the engine block on the back side.

    The belt arrangement from the CTS-V can also be modified to work well for use without a power steering pump, which is what we will run since we have the EPAS electric steering column, as well as on the 86 swap (above) and LS550 swap, both of which have an electric EPAS steering rack.


    This is an old pet peeve of mine - gutted race cars without a dash cover. Why does it matter? Two reasons - the cage's dash bar and an ugly mess of wires reflect up into the windshield and make a lot of glare. Second, it looks too low end, and this car needs to reflect well on Vorshlag, even if we have some leftover parts being used.

    Back in June 2020, the arguments over "using a dash or not" were played out and this tan dash skin was test fit into the car. This dash pad came out of another car and whoever removed it cut some part of the left side away. Not what I wanted but we needed to trim that side anyway, and we can patch that over and make it look good. We will also paint the tan sections black, and might even flock the whole thing.

    The dash still needed to be fitted, as it wouldn't slide forward due to the roll cage tubes in the way (see above left). So in late October I asked Brad to tackle this during shop hours. His detail oriented work made this look easy, and he had the dash trimmed and fitted in a relatively short amount of time.

    At this point we still had the OEM dash bar and brackets in place as well as our roll cage dash bar. This double dash bar setup would get pared down later, when the steering column mount was tackled. The dash skin still fits and will make a good place to mount switch panels, the digital dash, etc.

    continued below

    Leave a comment:

  • Fair!
    Project update for February 23, 2021: It has been 5 months since my last post in this thread, and as usual, a number of of things did not go according to plan (because our endurance E46 still isn't done!) We had more turnover in one position but we found a solid replacement in Zach, who's been here for months now. We had a couple of Covid scares where we all got tested, and one person in the shop actually got sick, but has since recovered. Then we had the craziest winter storm to ever hit the state of Texas in mid February and lost power for 3 days at the shop last week, shutting us down completely.

    Of course we are all frustrated that we haven't finished this E46 yet, but the shop is slammed with customer car work, plus one of our technicians is also manning the fab bench - and orders for those types of parts have ramped up even harder. We're still mostly working on the endurance car one night a week, but I have snuck in a few days of shop time here and there - and I'm about to ramp that up more to speed things up.

    There is a lot more work completed since the September 2020 "write-up", and I only got through June 2020 on that one, so I will tackle the last 8 months of work on the E46 endurance car this time. It is going to be a big one, so let's get started.


    One of the things I couldn't talk about until November of 2020 (due to an NDA) was the exact transmission we were using in this car and the '67 Mustang LS7 build. We got a pair of pre-production Tremec TKX 5 speed transmissions for these two builds, to test for track abuse, street use, and drag racing duty (on the '67).

    There is a lot of information about this all new, modern 5-speed transmission design here, but the basics are: it is a 96 pound box with multi-piece synchros, carbon blocker rings, 3 ratio options, and a 600 ft-lbs rating. This is not based on any existing transmission (like the TKO it replaces) but a modern, clean slate design. It fits in classic Detroit iron but we have made kits to fit this into several of our BMW LS swaps, too.

    We used our E46 endurance coupe build to develop the transmission crossmember and driveshaft solution for the E46 solution, and we put this into an E36 LS swap chassis we have on hand to develop that crossmember and driveshaft also. Running this in 8/12/24 hour races in our E46 should be a good test of this new box! More development on other chassis will come as time permits.


    We got the refreshed 5.3L LS engine back from HPR in late May 2020, and one of the things they noted when installing the Summit Racing oil pan was something we had to fix. The oil pump pick-up tube that comes with this pad was extended by almost .300" and the oil passages thru the pan were "ported". We describe the what, why, and how of all of this in this post.

    Evan was still with us then and I had him assemble all of the parts and pieces to this 5.3L during shop time. He installed and fixed the oil pan, the ICT billet valley cover p/n 551272 (necessary as part of our "Displacement On Demand" delete for this Gen IV LS aluminum engine), installed the SFI balancer, valve covers, and more.

    With the balancer installed (using an LS7 "long snout" bolt, then once pulled in place, using a normal "short snout" ARP bolt), he then cleaned up and installed the truck ignition coils and brackets. We used the long LS7 bolt to start the pulley as it engages more threads before it starts pulling. Then it was time to tackle the steam vents...

    The normal "car" LS engines use a 2-port steam vent crossover tube at the front of the block and a couple of block off plates in the ports at the back of the heads. We talked to HPR and they recommended a 4-port vent kit for use on this endurance car, so Evan modified a 4-port OEM truck steam vent to fit with our LS2 Dorman intake.

    It took a bit of work but he managed to make it fit, which saved us $100-200 for an aftermarket 4-port steam vent kit made with AN lines. We'll see how well it works. The intake was just mocked up above, as we needed to remove this during the drivetrain installation.


    In the last installment we covered the removal and replacement of all manner of bushings, bearings, arms, and sphericals in the rear suspension. The bent E46 M3 trailing arm stalled us out for a bit, due to a rusted and seized replacement. But the third arm we bought was good, and that went into the rear subframe assembly with new bushings and RTAB spherical.

    I asked our crew to put this finished E46 M3 rear assembly on the scales to get a weight on this unwieldy beast. 222 pounds was about what I expected, and similar to what a solid axle weighs if you think about it. But the advantages of beneficial rear camber and toe curves, and adjustable rear camber and toe settings, outweigh any possible weight savings of some dang solid axle!

    That's a bit heavy to lift by hand, but with the assembly lifted in place via our transmission jacks, we were able to get everything bolted into the chassis and attached the MCS RR3 triple adjustable rear dampers.

    The horsepower and torque we will be allowed to make in WRL GTO class is pretty low - around 300-330 whp, depending on our final weight - so we didn't spring for 1000 hp ($1000) axles. Instead we bought some cheap, new, OEM replacements for the E46 M3. These should be more than capable for the power output we are allowed.

    I'm glad we went with affordable axles because of all of the issues we had with trailing arm problems - one of the new axle stubs got stuck in the outer wheel hub flange and we had to just pull it out and replace the whole corner. We had some really bad luck in buying trailing arms, that's for sure. If you ever see one for sale with an axle attached - run away. It means they couldn't get it out and its stuck forever!


    The power this 5.3L should make will not stress even an OEM LS clutch setup, but we wanted to get something a little stronger. We looked at a couple of brands but this Stage 1 ACT organic should be easy to drive and more than strong enough.

    We didn't want to add the complexity of driving an unsprung or puck style metal clutch to the mix, or something super light (which means expensive). This should last for years if it isn't painfully abused. Of course I weight it..

    This clutch is made for use with an LS2/LS3/LS7 flywheel (but not the GTO version). I happened to have a Fidanza aluminum flywheel leftover from our LS6 engine in the original Alpha E36 LS1 build from way back when. This was cleaned up, the surface scuffed, and bolted to the crank with new ARP hardware.

    Now it was time for the clutch hydraulics. This Tremec TKX is setup with a 26 spline input shaft and a length similar to the old TKO. So we went with what we knew worked on those from previous use, a Ram HD hydraulic clutch slave cylinder kit. The RAM HD kit comes with the slave/TOB, a shim kit, a mounting stud to align on, a length of hydraulic line, and a bleeder for use right on the slave.

    Bleeding a clutch this way is nearly impossible. Instead we spec'd out a hydraulic feed line from the BMW clutch master cylinder to the RAM slave, then added a remote bleeder line as well. We had these built and added them to the slave.

    If the E46 LS TKX kits start to sell, we will offer all of this as a turn-key kit, with the hose that plugs right into the BMW master. Makes it super easy to do the install this way, in one step instead of a couple of test fits and trips to the hydraulic hose store.

    The Tremec TKX shares the bellhousing pattern with the TKO, so we used one of these bellhousings we sell. It is a beautiful cast aluminum and machined part and we have sold a number of these when we supplied TKOs to customers before.

    We aligned and installed the clutch and pressure plate, then the bellhousing was mounted up. To verify that everything fit we also installed the starter... and had an issue.

    With the bellhousing removed the interference with the nose of the LS starter was marked where it fouled. A few minutes with a carbide cutter on the die grinder and a couple of test fits later, it was all fitting nicely. Just something you might want to look for on these bellhousings when using the LS style starter.


    Normally we would go straight to Whiteline for our swaybar needs - and have used them on previous E46 builds, like our TTD/TT4 330Ci below. But their support for the BMW E46 chassis is less than complete. They make an adjustable 30mm front bar for the E46 M3, but when we went to order it they showed to be out of stock for months (and we actually have a non-M E46 front subframe/uprights anyway). The Whiteline non-M E46 front bar isn't adjustable, so that was less desirable. Whiteline doesn't make an E46 M3 rear bar at all, just the non-M. Which won't fit the E46 M3 diff (as we show below).

    So we looked around for another option, hopefully with the same brand of bar front and rear, with our unusual E46 non-M front and E46 M3 rear configuration. We also wanted some adjustments at both ends. Hotchkis had what we needed - they are stepping into the swaybar market with new offerings.

    We installed a Hotchkis swaybar kit on another car recently and were impressed with the quality. They make both E46 non-M and E46 M3 versions for both the front and rear, which are different. So we ordered the non-M front and M3 rear, to match our subframes and suspension parts.

    Now the first set of bars we got from them was ordered as a non-M E46 front and M3 rear, but they had mislabeled a whole batch of boxes and we got a non-M rear, which fouled with the M3's finned rear cover - this shouldn't fit like this - as shown above.

    We had to take some pictures of OEM swaybars to convince them, and had to wait a good bit to get the right M3 rear swaybar, but it eventually showed up. Again, Hotchkis is fairly new to the German car swaybar segment, but its a nice piece.

    I missed the work when they installed the "straight" E46 M3 rear bar, so I took it while writing this in February 2020 - and the rear shocks were removed, due to some rear shock tower welding. So this droop level is NEVER something you should ever see in an E46 rear suspension, as the shocks act as a droop limiter.


    We could have chased down some used LS2 factory fuel rails to fit our Dorman LS2 / 90mm intake manifold (615-901) but I wanted a full "return style" fuel system, with a feed line to the engine bay and return line back to the fuel tank (or in our case, the remote fuel surge tank, which I will show in another installment).

    We commonly use FAST or Holley fuel rails for most of our swaps, and went with the lower cost Holley "Sniper" rails for this install but, the crossover hose was too long...

    Evan shortened the long hose (above left) on the Holley 850001 kit and made it fit our LS2 intake and injectors. This will be fed via the Holley HP Billet Fuel Pressure Regulator 12-846.

    An ACDelco 90mm drive-by-wire replacement LS3/LS7 throttle body (12605109) was bolted to the manifold. We spaced the later "short" injectors with the FAST Fuel Injector spacer kit (146025-KIT), and had the OEM Gen IV 5.3L injectors cleaned and flowed at InjectorRx in Houston. Lots of sensors and grommets were installed on the intake manifold, too. This assembly would be installed after the engine and trans were in the car, to make room for the engine hoist / chains.


    With the refreshed 5.3L engine now assembled and ready to go into the car, and the clutch/bellhousing installed, the TKX transmission was bolted to the engine (I didn't get pics of this step). On June 18th, 2020, Tim, Evan and Magan installed the engine and trans as a unit.

    We were able to use the engine leveler and just stuffed the whole thing in from the front, with the radiator support and bumper beam removed. Magan was using a floor jack to line up the transmission and keep it from dragging while Tim and Evan lined up the engine mounts.

    Takes a bit of adjustment (there are slightly oversized holes in the engine mounts to allow for this) but it fits in there perfectly. The newly powder coated E46 TKX crossmember bolted in place to hold the transmission in.

    Normally we build an E46 with the Tremec T56 Magnum or the slightly longer (1.5") T56 Magnum F - which is the new size that mimics the 1998-2002 F-body T56 (Camaro/Firebird) length with the upgraded magnum case and guts (700 ft-lb rated). Those have shifter distances that line up with the E46 shifter hole, but they are heavier and more costly. We didn't have either of those lying around, but we did have the 5.5" longer T56 Magnum XL on hand, which we use in S197, S550 and 86/BRZ swaps. As you can see above the TKX much shorter than that. It even has a "bellhousing to shifter" interface is about 2" shorter than the T56 Magnum.

    Not a huge deal, and as you can see above and below the TKX shifter hole is about 2" forward of the factory E46 shifter hole. It might complicate a street car's interior, but for a race car, this lighter and less costly 600 ft-lb rated TKX is still a great choice.

    continued below
    Last edited by mylesloan; 03-01-2021, 11:30 AM.

    Leave a comment:

  • Fair!
    continued from above

    New inner/outer tie rods went on along with the de-powered steering rack, new Lower Control Arms, and the LCA bushings from Whiteline.


    Like all BMW E46 chassis, the rear subframe mounting points on the tub need reinforcement, so that was a big task I saved for the new guy, who was a welder for use for a number of months. We do these jobs periodically for customers and I like to break in a new tech on a shop car instead of on a customer's car.

    In the last week of May 2020 we made room on the lift for a couple of days to tackle this work on the clock. Brad and Evan showed the new guy how to do it and helped remove the fuel tank and rear subframe.

    After the chassis was cleaned of paint and undercoating (the least fun part of this job) the CSM reinforcements were bolted into place and it was time to TIG.

    The 6 plates were TIG welded, seam sealed, primed and painted within a couple of days. While the OEM fuel tank was out I went and power washed that to look as good as new.

    One of the areas on the chassis I have personally seen fail (at least on the E36 chassis) is at the RTAB cassette mount. So I asked Myles to make a tracing of the OEM mounting holes and shape, design a CAD drawing, then cut a pair of reinforcements. With one small tweak we had a new product, and we are using our chassis to test it out on. Which is part of the reason why we're building this car.

    With the RTAB reinforcement welded in, seam sealed, primed and painted it was finally time to install the upgraded, powder coated, and stronger E46 M3 rear subframe and diff. This move let's us go from an open 188mm diff to a limited slip 210mm M3 diff.


    As you loyal readers know, we're upgrading our E46 330Ci to use an E46 M3 rear subframe - brake to brake. Gives us the stronger 210mm LSD diff housing, stronger M3 trailing arms, beefier M3 hubs/axles, and bigger M3 rear brakes. We finally had the rear subframe assembly reinforced subframe, bushings installed, and new sealed sphericals installed - so this was a complete weight for the unit, without axles. 222 pounds of aluminum and steel.

    A big hunk of that 222 pounds is the diff (95.4 pounds), another big chunk are the steel trailing arms (68.6 pounds).

    There were several upgrades done along the way to get this rear M3 subframe assembly read for endurance racing - and I'm sure we'll see something else in track testing. We have shown the subframe blasted, seam welded, reinforced, and powder coated in previous forum thread posts.

    This assembly went into the car with SPL Parts spherical rear camber links, shown above. This is a part we have used on a number of BMW builds and we know the guys at SPL very well.

    This all went into the reinforced chassis without any issues, lined up and bolted up. It was time to put it on the ground and see how it looked...


    It didn't take long to see the issue with our first of FOUR different left rear trailing arms - it was bent (see right vs left pics below). This arm was from a rear subframe I had purchased along with a car more than a year previous, so it was too late to cry sour grapes.

    With the naked eye you couldn't see any wrinkle or bend in the hollow cast steel arm - it wasn't until we had a replacement arm next to this one that the bend was obvious. Not a part you try to "fix", either. That bent arm is scrap at this point.

    Luckily I had another E46 M3 rear subframe assembly I had bought in late 2019, so that arm was pulled for use on the team car. But the bad luck just kept coming. As the rear wheel hubs were being removed for a rear wheel bearing replacement, it just broke. Yes, we know how to do this job and have done it many times... it was a somewhat rusty arm, so that didn't make it far. Wasted probably 2 hours on this one before we got to this point.

    So I bought another E46 M3 trailing arm, and this one *came with the axle. It also came with a single Ground Control spherical RTAB, which Tim removed - we're trying to test the Sealed Spherical we had installed on the previous bent trailing arm. (*NOTE - if it comes with the axle it is because they couldn't get it off!)

    Tim and Magan fought with this 3rd trailing arm on the bench - the axle didn't want to come out. They got the upper and lower sphericals replaced and the sealed spherical RTAB, and I told them to put it on the car and we could use a slide hammer and heat on the axle...

    Once on the car a couple of weeks later (remember: we're only working on this one night a week for a few hours, at best) they tried heat, slide hammers, but that axle will NOT come out of the hub. The end was ruined before it got to us (at the junkyard that sold it to me). I've since learned of a trick to get this out - soaking the axle in some "magic sauce" (50/50 mix of Acetone and ATF fluid), which we will do later to salvage this trailing arm.

    But at the time I was getting sick of this damn trailing arm holding up the build and burning up hours - the bearings and RTABs were moved to each arm, the brake backing plate modified each time, etc. So I kept "throwing money at the problem", and bought bigger tools and more trailing arms until we had a setup that worked.

    Forth time's the charm! This was the best looking used trailing arm so far, and one night Tim got that one swapped to the new bushings, RTAB, hub removed, and on the car. Then he and I got the snap ring extracted, then the wheel bearing pulled.

    Next up the arm comes off the car, the new wheel bearing gets pressed in, then the snap ring, then the hub is pressed in, then it goes on the car, then it gets the new axle for that side. THEN the car can go on the ground and get ride heights set. Whew! That whole process was some nonsense, but we should get at least 2 spare hubs and a full spare trailing arm assembly out of the spare parts, once we soak arm #3 with the "magic sauce" and get that rusty axle out.


    On the upper arms there are rubber bushings on the inboard side. Rubber bushings are the Devil - they allow lots of deflection under lateral and braking loads, which we don't want. So we invested in these Rogue Engineering spherical bushed housings for this location, shown below left.

    Tim used some sockets and the 20 ton press to push out the old rubber bushings and housings, then used an old mechanic's trick - tossed the Rogue spherical housings in the freezer for a few hours.

    That shrinks up the bushing and allows it to slide into place in the upper control arms nicely.

    The Rogue housings have a face on one end that you press to the control arm. The other end has a groove for a snap ring, which secures into the arm. Inside this housing is the spherical bearing, with bushings that press inside that to allow the bolt to fit and provide articulation. Above right is this end of the re-bushed upper arm bolted into the E46 M3 subframe.

    The trailing arm has two sealed spherical bearings from the factory - and we replaced the old units. On. All. Four. Trailing. Arms. Getting the old units out was relatively easy using a BMW specific press and cup tool set we have.

    Pressing in the new units is pretty easy - they just press in with the same tools. Those shouldn't be a problem for a long time on the final arm that went into the E46. They don't wear as quickly as "open" spherical bearings do, which some racers like to use. We try to use sealed sphericals whenever possible - the rubber seal keeps rain and road grit from destroying the metal ball and surface of the spherical, just as the factory intended.


    There is a LOT more work completed, but the "write-up" was taking too long and so I cut it short here. Next time I will show the 18x11" wheels, rear unibody and front fender cutting / clearance work for the Clinched flares, and the "real" 5.3L LS V8 and drivetrain install.

    Sway bars, and the ensuring drama that a new brand brought with it. The rolled radiator mounting, steering wheel / hub / quick release, replacing missing things like door latches and handles, and more.

    Thanks for reading!

    Terry @ Vorshlag
    Last edited by mylesloan; 09-24-2020, 02:06 PM.

    Leave a comment:

  • Fair!
    Project update for September 23rd, 2020: It has been 6 months since my last post here, and not a lot of things went according to plan. We got crazy busy during the pandemic, lost some manpower, but we are still working on our E46 endurance car a little every week. I spent part of Labor day weekend writing this update to catch us up to the present, which helped me realize I needed to order a few missing parts, as well as update some product entries for things we sell for E46 models. Then I got busy and had to re-start my write-up again.

    There is some progress to share, with some "backwards" progress in one area, and nothing happened as fast as we liked. As racing resumed, so did the pro racing support schedule for two of our team members, Tim and Magan, who regularly travel to events for trackside support. "Luckily" none of the other Vorshlag shop cars are complete so I wasn't out for almost any of 2020 going to races (this actually sucked). More time to work on this car - and more motivation.


    After our show-and-tell with the E46 we pulled the mockup engine out for the last time. We had the new transmission crossmember developed, test fit two new oil pans, and learned a lot with this task.

    Pulling the radiator support out makes for a FAST drivetrain removal (engine and trans together), and I encourage any endurance racing team to make that happen on their cars. Removing engines is often a necessary task.


    So the dash bar (above) that came with the Hanksville cage kit was made to go pretty high up and would pretty much preclude the use of the dash. And I really wanted to keep the OEM dash pad, for appearances as well as to make for better "glare protection" and gauge visibility on sunny race days. So it was time to make some changes to the cage. We looked at the OEM dash bar, which has all sorts of integrated bracketry to hold the dash pad.

    In March on one of our work nights Tim, Magan and I tackled the dash mockup while Myles was welding on other parts of the cage. We removed the Hanksville dash bar and mocked up an OEM dash in the car (we have two - tan and gray ones). There was going to be interference and notching needed but there wasn't an elegant way to mount the shell.

    We removed the dash bar structure from the dash shell and started hacking away at it. To fit it between the two main A-pillar down bars we had to cut the OEM dash bar in half.

    We cut the main bar to the right of the steering column support, notched the ends to clear the down bars, and put it into the car. Then tack welded it back together.

    This way the dash pad has some of the OEM structure - which is a lot better than how some dash pads get installed. I cannot stand a floppy dash that is bouncing around willy nilly.

    Since we compromised the structure of the bolt-in dash bar (we really had to hack up the ends) as well as cut it in half. We built a new straight dash bar to mount just next to the OEM bar. This is going to be hidden under the dash but this one has real structure and ties into the cage in case of a side impact. We will tie the OEM bar to this one, for the structure needed to hold the column. We still need to notch the plastic dash pad to fit around all of this, but I will show that in a future update.


    The composite Seibon hood (24 pounds) is considerably lighter than the stock steel hood (42 pounds), but it is weaker in some ways also. When some of the crew were man handling the hood into place back in March they only had one bolt on one side fastened and somehow with the hood struts installed on that hinge it was tilted, which cracked the mounting flange for the hinges on one side. I've seen similar damage done when using (mostly aftermarket) gas lift hood strut kits.

    I was less than thrilled, but "stuff happens" and at least it wasn't a customer's car. Evan extracted the threaded insert plate that had pulled out and sanded the areas to be repaired with more layers of glass and resin.

    He cut a space for that into the composite then used fiberglass mat and resin to cover that plate and reinforced the whole area. A little primer and it is as good if not better than new.

    We installed the repaired composite hood for a while with one new OEM gas lift strut on one side, but it still felt like the hood was going to fly off when we lifted it up. Just sitting there with the hood up it was bending that side, so we had to do something different. I had an idea...

    In late August I installed this S550 Mustang hood prop rod setup. This is an aftermarket, stainless steel version of an OEM prop rod made for 2015-up Mustangs, which was easy enough to install. I added an M6 threaded insert to the radiator support and bolted it on during one of our work nights. Still might tweak this a bit after we get the cold air intake hose and airbox in, but this way we can hold the hood up and NOT have the gas struts trying to bend the hood in half.


    This car was stripped of the pedal box. We had a loaner for a bit to do some initial mock-up, but we needed to buy our own set of E46 manual transmission pedals and I found this on eBay - the home for junkyard parts.

    These bolted in back in late February, but we have not yet installed the throttle pedal. We're using a modified LS3 Corvette Drive By Wire pedal compatible with the Holley Terminator X-Max EFI system we chose.

    We have made a lot of these LS3 brackets for various one-off LS swaps in the past, but for the E46 we are going to create a production pedal bracket kit - like we did for our S550 Mustang LS swap (above). We might incorporate the mounting into the Prius steering column center bearing adapter mount, too. More on that soon.


    Normally when we take a cage job we can knock it out in a few weeks. Or sometimes it is built in stages over the course of a major build - like when we have to do a lot of wiring or interior work, we want the door bars to go in last, as they are a struggle to work around once in place.

    In this case, we're doing the cage work at best for a few hours one night a week, with one fabricator who has a lot going on (Myles). He is also an engineer, CNC operator, and just had his first baby - so he's been pretty busy! Since our last post he has tackled more of the TIG welding and Tim has helped him on a few custom bars (changing the "X" bar we ordered to a NASCAR bar on the passenger side). We did add invest in an air-over-hydraulic kit for our JD2 tubing bender, which makes new tubes easier to make and bends are more accurate.

    So the cage is making progress, just slower than we would on a customer's car - because we don't have 8 hours a day or a full time fabricator to tackle the cage work on this "after-hours" employee build.

    The main tubes are all in place now and we are just waiting to finish weld in things like the dash bar, an FIA vertical bar we are adding, and one roof bar.


    We have been talking about using an "Electric Power Assist Steering" (EPAS) column in this car since the beginning but I have not shown that yet. Why? because unlike aftermarket supplied units we have used in the past, we're trying to do this with cheaper OEM based column.

    The aftermarket EPAS unit above worked well enough in this V8 E46 M3, and I got some good first-hand experience with this on track this January. But it was expensive ($1800-ish) and required a lot of work to join their electric motor to the E46 steering column. It does have a steering force controller on a dial, which is nice, but it wasn't working 100% of the time in our track test. We're chasing issues with that now.

    Instead we're trying to make a steering column from a Toyota Prius model retrofit completely into our E46 330 endurance chassis. This could make for a lot less hassle during the install or for replacements later (expect everything to break on an endurance car at some point). We have researched several units and some racers have used the 2004-09 Prius unit (above right). But we have very different height drivers in our car, so the tilt/telescope feature of the 2010-14 Prius might work better for us. We bought both to test with.

    Myles has designed and cut out a couple of different brackets that were bolted or tack welded to the BMW steering column mount, to test both the early and late Prius columns. The column was "clocked" so that the motor was not down by our legs this time, as shown above.

    To complicate matters the chassis we started with came with no steering column at all - it was pretty stripped - so we didn't have a good gauge of where the steering wheel should be. So we paused the steering column testing for a bit to wrap up the E46 seat bracket base, get the seat installed on a slider as low as possible, then proceed with more Prius steering column mock-ups.

    It wasn't until the seat was mounted and the cage largely complete (late April 2020) before we could "test sit" the column. Above is the early tilt version shown at two tilt heights. We could never find the correct Toyota wiring diagrams and pin-outs for the later tilt + telescoping version, so that version will have to wait. We got some schematics, but they were wrong and didn't match the 2011 column we bought.

    Tim sourced a Flaming River U-joint that ties into the base of the steering column's intermediate shaft splines and goes to a 1" DD shaft. We then connected the other end to another shaft that will have our BMW 54 spline U-joint at the steering rack. A "center bearing" at the fire wall is needed to keep this multi-piece shaft lined up (a support bearing at the firewall is normal).

    We have the center bearing and will fab up a plate to cover the MASSIVE hole in the firewall from removing the OEM bits there. We have since wired in the early Prius column and await getting the car back on the ground to test this further. I made some progress on the custom, bolt-in "filler" panel that will mount the center bearing, which I will show next time.


    Not much to show here yet - just that we ordered and received our Painless chassis harness kit with fuse box as well as the Holley Terminator X-Max harness and computer to run the LS engine.

    We will use the Painless harness to replace the missing OEM chassis wiring harness and fuse box, and the Holley system will tie into that to control the engine. Will share more when we have progress to show.


    On a work night in late May 2020 Tim started tearing down our E46 steering rack to "de-power" the hydraulic power assisted unit. This will remove some resistance internally and allow the EPAS column to add the power assist, removing high pressure (and flammable) hydraulic power steering fluid from the car.

    After we power washed the exterior of the rack, Tim tore it down like he would any Miata rack - which he has de-powered many times. The pinion was removed, then the rack portion. On the horizontal shaft in the rack, the separating piston was removed.

    This is what allows for the assist - as hydraulic fluid pushes on the piston left or right. With that piston removed - viola! - it is de-powered. He re-assembled the entire unit with grease (the pics above, shown out of order) and then got it ready to go back into the car with new tie rods and boots.


    I showed the Horsepower Research 6.3L cathedral port LS engine build slated for our endurance car here in a previous installation. That was completed during the 'rona, but I stole it for use in my LS550 swap development, shown below. That project car is on the final stretch and we needed a ~500 whp engine to get this going for Phase 1 of that build.

    This 6.3L LS6 will be used for initial testing on the Mustang then it will go to it's true home - our Endurance E46 here. In April we took our "backup" engine and rebuilt that, also at HPR. I horse traded for an aluminum 5.3L truck LS engine and it has similar cathedral port heads, just with a smaller displacement.

    Turns our this engine was pretty worn out - pistons, rings, and bearings were worn but not overly damaged. The pistons were replaced, as were the rings, bearings, and more. Didn't need an overbore, just a "kiss" of the hone, some bearing setup, a spicier camshaft / valve springs / retainers / locks, new roller lifters, custom pushrods, and reassembly. The worked happened during the biggest parts shortage period during the pandemic and HPR got this done unusually quickly, since it needed so few parts. It was done in late May and we didn't get it fully assembled and into the car until June.


    With as many sphericals as we have on this chassis, normally you'd think we would go right to a spherical Lower Control Arm bushing at the factory "lollipop". In the past we have used Powerflex 3-piece LCA bushings, which have to re-use the OEM lollipop casting. On this car I wanted to do some long term testing with the Whiteline W52519 LCA bushing and housing kit. It comes with the same 3-piece (rotating) urethane bushings with new lollipop castings.

    We installed these with new non-M E46 Lower Control Arms, which have new ball joints in both locations. This will all be a test to see how the OEM style arms and poly bushings work out on the endurance car. A one-piece poly bushing would be a BAD choice here, but with a 2-piece bushing it allows for proper articulation.

    Long term we might have some fancy doo-dad tubular arms with spherical ends - but the costs go up by a factor of at least 5 over what we have here. Having driven E46 cars with "magical" tubular arms and geometry fixes it didn't seem life changing as some claim.

    Again, it is something we can likely test down the road to see IF IT MAKES THE CAR FASTER. If it does, we will do it. If it has drawbacks (like cost, reliability, etc) we will fall back to this setup.

    continued below

    Leave a comment:

  • Fair!
    continued from above

    Out back was a bit trickier. MCS wanted us to run their inverted, eye-to-eye style rear shock with a 22mm shaft and coilover spring mounting, using a dual / helper spring setup to keep the tire loaded - even at full droop.

    This required the use of the MCS "eye" upper shock mount, which bolts into the stock shock tower (see below). Brad mounted that and I was happy with how much inboard wheel clearance we still had. Whew!

    This type of spring mounting can sometimes compromise inboard wheel room - a coilover rear on the E36 chassis absolutely will eat up tire room, but the E46 chassis does not suffer from this space constraint. We will need to reinforce the rear shock tower to take full suspension loads, instead of just damper loads, however. We have some ideas and will share that work in a future update.

    Brad handled this MCS install in early February 2020, which let us mount the 17x10" wheels and roll the car out of that back bay for the first time in months. Big step, seeing the car down on 4 wheels and rolling again!


    Shortly after getting the suspension installed we were able to get the E46 over to a 2-post lift and up in the air.

    I asked Brad to temporarily tape the Clinched flares (we showed last time) to the car at both ends on the driver's side. These are made to be "trimmed to fit" the contours of your car, and this is where the look and fit of these will improve. For now we're just taping them in place.

    This let Jason come out and inspect the clearance inboard, outboard, and relative to the flares. These flares are going to be big enough for our 18x11" wheel and 315/30/18 (or thereabouts) 200 treadware tire package.

    The test wheels shown here are NOT our final race wheels, and they are already 10" wide. We're looking to add another inch of wheel width and a good bit more tire. The "stock vs flared" pictures above should show how much room we gain with these flares. Jason was able to spec the wheels so that the same set can be used front and rear (fewer spares needed, and they can rotate) with a 12mm spacer up front, which is normal for most BMW wheels. These wheels were ordered from Forgestar before their additional bespoke wheel charge came into effect, which was a bit of a surprise in March 2020 when that came down.


    We had been debating head lights to use and how to mount them. The factory "radiator core support" (shown below) is the easiest way to mount the headlights, but it has a bunch of structure we don't need. We have bought a number of these over the years from the import suppliers and they all worked just fine. Looking through our pile of spares we had another brand new one in stock, so we decided to splurge the $55 already spent and use it.

    Our car didn't come with one, as it had been in a front end hit. These are pretty common to replace after any small accident, and BMW keeps them painted black no matter what color E46 they made. It didn't take Evan more than a few minutes to bolt this in place, then we started looking at the extra plastic clips and mounts needed to bolt the headlights in place.

    Instead of ordering a half dozen special clips from Germany we decided to add nutserts into those square holes in the core instead. Evan drilled the square holes round, then installed some M5 rivnuts. We used some old headlights to make sure they lined up and they did.

    The radiator support was then cut up quite a bit - looking for room to fit the radiator. Our goal was to open up a narrow spot and then shove a wider than stock radiator and roll it forward into all of this area we added by making a tubular bumper beam. Unfortunately the headlights themselves are wide and we don't gain a lot of room between the lights to roll the radiator into. But we did remove a lot of structure that was blocking airflow.

    The "mock-up" headlights we had on hand were fitted in place when the rivnuts were being added. These looked rough, and were some old OEM units we had leftover from a customer's build when we installed new headlights and turn signal housings on his M3. Tim wondered - can we clean these up and use them? I was doubtful...

    Now for headlights I was ready to spend a few hundred on some nice aftermarket replacements but these aren't really needed on this race car. The halos, the smoked turn signals, not really worth it. These are some I purchased for another E46 we covered in this same thread, years ago.

    Brad brought out his headlight polishing kit and got started wet sanding and polishing the lenses...

    They cleaned up pretty well, surprisingly. Enough to not be an eye sore for our "show and tell". I still might buy some new lenses later (they are amazingly inexpensive) and we can install those with some very bright LED bulbs from Diode Dynamics. Possibly even some yellow XPEL film to protect the new lenses. Will show more here another time.


    Many months of work and a bit of a thrash in January and February came to a head when we got the car on the ground, on MCS dampers, with an LS engine and headers installed, wheels and tires on and rolling, headlights, M3 bumper cover, bumper beam, and the red steel hood installed.

    Since we had the car on the lift we installed one of the Sparco race seats, a radiator, stuck both doors in the back, the heater box (which I haven't showed yet) was set inside, and the electric steering column (also not shown much) was bolted in place. This car has both front 14" rotors and one of the Brembo calipers, and the E46 M3 rear rotors are installed. All of the tubes from the cage kit were inside the car, if not welded in place already. Still has the old non-M subframe and diff, for now. We even loaded the clutch, flywheel and pressure place inside. A Mishimoto radiator was set on top of the engine, and a 22 circuit wiring harness was placed into the trunk, too. Then we got this weight.

    2112 pounds was lower than any of us guessed, but a decent amount. We're still missing the the transmission + bellhousing, windshield, driveshaft, swaybars, plumbing, fuel tank + fluids, and the larger E46 M3 diff housing is going to be heavier than the medium case in the car now. But the steel hood and trunk are being replaced with carbon, which will save a little. So we're off by 200-300 pounds. Still, it was a very encouraging number.

    Due to this latest weight check we have a good idea of where we will end up now, and this is helping us make smarter decisions as we wrap up the build. We will of course keep taking weights and posting them, even if the car is incomplete. These data points have been helpful to some.


    On March 3rd I was working late and a freight truck arrived at 7 pm, in the dark, while raining. I had to scramble a bit to get the fork lift hooked up and unload this big pallet of carbon fiber parts. I dubbed it "The Carboning!" and was as excited as a kid on Christmas.

    We unloaded the pallet the next day and unboxed all of he Anderson Composites and Seibon parts. These are two sides of the same company, with Anderson being their domestic car arm and Seibon the import car arm. For our S550 Mustang I received a carbon trunk and carbon doors, shown above.

    For our BMW E46 project we got a carbon hood and a carbon trunk. The quality and finish on all of these was great. These Seibon pieces are not "dry carbon" motorsports parts (which they also make) but their more affordable carbon-over-fiberglass / shiny gel coat versions. Still lighter than stock, but not as light as you could see.

    Of course we took weights on everything. On the trunk we went from a 27.7 pound steel unit to a 15.6 pound carbon unit. That's a 12.1 pound drop, or a savings of 43%.

    The steel 330 hood was 44.5 pounds, and the carbon version was 24.2 - for a drop of 20,3 pounds and a savings of 46%.

    In addition the new hood is the "bulged" M3 style and includes a set of carbon grills (which are removable) as well as four massive, carbon vent panels (also removable). The outside carbon surfaces are very glossy and the weave is laid out nicely.

    Brad installed the Seibon trunk in about a half hour, just needing to shim the hinges a bit to get the body lines perfect. This required zero sanding or trimming of the actual part, which is pretty rare for composite parts.

    Jason and I spent about an hour and a half fitting the hood. This was mostly due to the poorly aligned front fenders, which had huge gaps to the steel hood. We slotted some of the mounting holes there and got the body lines pretty darned good, too. Really looks good with this carbon installed, of course.


    This car was missing anything and everything of value, and that included the pedals. After getting a loaner set that I had to give back I broke down and ordered a clutch/brake pedal assembly for $102 shipped from eBay. Tim got those installed on a work night pretty quickly. Installing those allowed us to bolt on the E46 brake booster we had, on the other side of the firewall.

    We found an SSR fiberglass sunroof panel that I had ordered back in 2015 for another E46 coupe, and this will be used on this car now.

    Another missing part on this chassis were the rear tail light housings, along with the trunk mounted reflectors. I bought a set of the brighter LED versions for this E46 coupe.

    Tim installed these into the carbon trunk in early March - nothing tricky here, just a straight bolt-in. As we have done before, we will "direct wire" these around the CAN network that normally controls these brake/tail/turn/reverse lights. We're replacing the entire wiring harness on this chassis.

    This set of LED tails + carbon trunk really set off the back of the car. We have a new, fake, custom license plate we will add and show next time, too.


    That's a big chunk of work to cover this time. We have other work that has been completed but we're not ready to show all of that just yet - like a brand new crossmember to support a new transmission for this E46 LS swap. Lots of parts have arrived for the front suspension, too.

    New inner/outer tie rods, Lower Control Arms, and these LCA bushings from Whiteline with a 2-piece bushing (that allows for proper articulation). We're using this car as a test bed, remember - and this is a new part to us. Rear subframe reinforcement work needs to be done, exhaust needs to be built, and more.

    At the same time as this E46 endurance car update was written we also posted an update on our GMT800 shop truck build thread, which went through a ton of changes. You can read that here.

    Until next time... thanks for reading!
    Last edited by Fair!; 03-24-2020, 07:49 AM.

    Leave a comment:

  • Fair!
    continued from above


    We had a bit of a dead line for a "show and tell" meeting with a supplier in February 2020, who needed to see this race car. It was a good incentive for us to push harder and get more things done to the E46 - like installing an LS engine, installing suspension, having the cage mostly done, nose mounted, etc.

    We had the "backup" aluminum 5.3L long block up at HPR but brought it back and mounted a real road race style oil pan to the engine, then stuck it into the car.

    Of course we had a bunch of LS swap parts we sell to use for this, but luckily we had some early prototype headers, our original prototype mounts, and a few other leftovers to use. This Summit steel road race oil pan above fits with miles to spare - something we wanted to test on this E46 swap anyway.

    We built our shop 2015 Mustang #LS550 swap around this oil pan, and it seems to fit anywhere the 1998-02 Camaro pan or any of the Holley LS pan fit. We will test this in this road race setup on both the 5.3L and the 6.3L stroker that will go in later. With a wet sump oiling system and an Accusump, of course.

    Great fit on the kick-out style oil pan, so we'll keep that. The oil filter mount comes off for use with a remote filter and oil cooler, which we will show later. Found these tall LS valve covers with the "CHEVROLET" script, and we will use these with remote coil mounting.

    This is a Gen IV truck engine - which all come with DOD features we have to bypass. This requires a unique upper cover (ICT Billet, shown above), and Gen III style front cover, timing chain, cam shaft, and lifters. We're going to do initial testing with this 5.3L so we're getting it ready.

    Then we installed the Dorman "LS2" intake and a 90mm DBW throttle body. Then a set of our E46 stainless long tube headers.

    That's as far as we got for the show and tell - the motor has since been removed and then reinstalled with a new transmission.


    As I mentioned last time, we had a few 210mm M3 diff housings (which come with limited slip differentials from the factory) and two complete E46 M3 rear subframe assemblies, as shown below left. Everything on the E46 M3 version is stronger - the differential housing, trailing arms, rear brakes, and more. The E46 non-M rear subframe (see below right) has a number of disadvantages.

    In the long run it will be more cost effective for us to convert our 330Ci chassis to use the E46 M3 rear subframe and M3 diff than to convert the 188 mm Medium Case E46 housings to limited slip.

    Since none of the "non-M" E46 cars ever came with a limited slip, and many of those medium case housings have a ring gear welded to the diff case, it can get pretty costly to convert one to limited slip. I've done this conversion on non-M E46 cars a few times and it is always shocking how costly this is to do. The differential mounts on the non-M case are also different, and less than ideal (see above right). The available gear ratios on the larger M3 housing also work better for our V8 engine. We will be beefing up even the M3 bits, and will show the various steps below.


    We have a few complete E46 M3 rear subframe assemblies, brake to brake. We buy these when they come up for sale, and in one case we had a rusty version that was in a northern car that we picked up cheap. We took the ugliest of our available rear subframe assemblies apart to use for this project.

    This involved removing all of the subframe bushings, shown above left. This took a little work but they came out relatively uneventfully using our many BMW specific bushing tools.

    You can see the rusty surface of this subframe housing, above. It wasn't deep rusty, just ugly surface stuff. I took this and dropped it off to be bead blasted in November 2019. We got it back in mid December but didn't get a chance to work on it further until January 2020.


    While the subframe was coming apart we decided to test a new product we had found. The Rear Trailing Arm Bushing (RTAB) on the BMW E36 and E46 chassis is a complicated joint that has to pivot and rotate in 2 different axis.

    We don't use polyurethane in this joint, ever. Instead, for the past 16 years we've been in business, we press in an OEM rubber bushing + our RTAB "limiters", which we machine from UMHW for its self-lubricating properties - as shown above. This limits how much toe change can happen with full articulation of this rear trailing arm. A better solution for a race car is to use an aftermarket spherical metal bushing assembly here. The former works well on street and dual purpose cars, the latter not so much. A little road grit + rain will quickly wipe out an all metal bushing located so close to the ground.

    For this build we wanted to try a new "sealed" spherical bushing that Jason found. This should give us the best of both worlds. Water proofing a spherical bushing (like BMW does for some other rear suspension locations) would allow for full articulation in 2 axis, without the rattle and bang that worn sphericals give you in a short amount of street driving. Tim removed the M3 rear trailing arms (above left) from the subframe, then Myles and Jason pressed out the old bushings.

    We found an OEM replacement sealed spherical that was almost the right size and we made it work in this location. It wasn't easy, and it took some custom machine work and some other compromises. For now we're not releasing what we did or offering this as a kit to sell until we can test this car on track. With a little bit of work we think we can make this easier to install for the DIY crowd.

    We installed and fitted the bushings on the two sides two different ways, testing two methods. It was "more than a press fit" getting the spherical housing into the Rear Trailing Arm. Once we got the fit where we liked it, they were both pressed into the arms with the giant C-clamp bushing press shown.

    For now this isn't an easy "DIY" job but we're working on some other ways to make this work better. The articulation is perfect (above right) and should be the right solution for E36 and E46 chassis cars, once we can make the bushing more perfected for this application. More on this later.


    There were a number of things I wanted us to stitch weld as well as some reinforcements to make.

    Up first was a pair of brackets that held the rear swaybar. Nobody makes a reinforcement kit for the E46 M3 subframe so Myles drew up and CNC cut out these plates above.

    Likewise the two rear differential cover mounting brackets looked a little underwhelming, so I asked Myles to make the brackets above.

    After he made some cardboard templates and we discussed a number of tweaks it was time to turn them into CAD drawings then CNC cut them on the plasma table. After they are cleaned up and bent they fit these locations well. After showing the picture above a number of folks reached out and we have made this E46 M3 kit available.

    Myles TIG welded these reinforcements to the 4 locations we wanted to strengthen, then stitch welded a few spots that the factory skip weld. This is part of why we bead blasted the whole subframe - it makes for cleaner welds, shows any flaws hidden under the factory paint, etc.


    After we got the rear subframe back from powder coating it looks beautiful. We rounded up a set of Powerflex "race polyurethane bushings for the subframe (4) and differential mounts (3). Some might find our choice of poly unusual, as there are Delrin and even aluminum options for all of these locations. Well having done all of that before we knew that this option would give us the least NOISE while controlling any unwanted movement. Aluminum bushings in particular make for a lot of loud crashing and banging, which can be unsettling in an 8-24 hour race, over and over.

    Brad pressed in the bushings into the housing (above left), which had already been removed before blasting. The diff housing was then tackled with some special tools we have just for these 3 locations.

    Two of the bushings for the M3 housing are in "ears" that extend out from the aluminum rear cover. These are relatively easy to get to. The front bushing is near the pinion flange and goes in the right side - it is pressed into the subframe assembly, and is a little trickier to get to. The diff housing then bolts through this bushing to mount the front.

    With all of the bushings pressed into the subframe and diff housing it was time to joint them together, shown above and below.

    This selection of "harder" durometer polyurethane bushings should provide the control needed between these two pieces, which normally rock and roll around on very soft OEM rubber bushings. This movement, of both the diff to the subframe and the subframe to the chassis, is what causes so much flexing of the sheet metal tub - which leads to cracks that have to be repaired. We will fix this by adding reinforcements to our chassis in a later update, of course.


    One of my goals for this project it to develop new products - and one area we have been pushing into lately is seat brackets. I moved us into this arena reluctantly, but since many of the chassis-specific seat base bracket offerings out there are so terrible (too tall, too flexible, not safely built) that I felt we were doing the community a disservice by staying out of this area.

    I wrote this forum thread last year explaining the "what, why and how" of our unique form of seat brackets. We have made these for 5 different chassis now and will be offering the E46 versions soon after I post this. We make these to bolt to the chassis, have mounting holes for lap and anti-sub belt anchors, and leave a swatch of metal that the end user drills and bolts their side brackets (fixed) or sliders to. All of these designs are minimally tall and have reinforcing ribs underneath, and we make them 100% in-house with CNC cut parts, TIG welding them on production fixtures.

    We normally take manual measurements of each chassis' four factory mounting holes, but this time we were willing to try some new technology - 3D scanning. A helpful sales tech came by to demo his scanning products and used this chassis for the test. What it gave us was a point cloud that we could then translate into a CAD design. Don't know if it really saved much time, but it was cool watching this tool being used.

    Myles turned that into a working prototype, which he CNC cut and we tested in the car (above left). The E46 chassis is pretty narrow and what he realized pretty quickly when this prototype was placed in the car is - we usually offset a racing seat pretty far towards the tunnel. The factory steering wheel isn't even centered on the factory BMW seat. So I worked with him on version 2, which has this offset built in, that he cut, tested, then welded in the reinforcing ribs for (above right).

    Tim worked on the sliders and side brackets, which were tested on the seat, then the holes were transferred to the bracket (above right) and the sliders + brackets were bolted into the car. So we have one seat mounted. As soon as we make the passenger side version (they are sometimes mirror images of the driver's side, sometimes now) we will release this as a bracket to sell.


    For the past several months our E46 had been up on jack stands and stuck in this cramped work bay. This was because we had removed all of the OEM suspension and had only mocked up up one front corner with a strut/spring/top mount. This let us work on the big brake kit there but we needed to get this car down on the ground and mount up some wheels and tires to move forward in the build. This meant we needed a set of coilover shocks.

    We had put out the ask for a little while, and MCS came through in a big way. Getting triple adjustable MCS dampers for this car was the culmination of a lot of hard work, a long record of MCS sales and race wins using their parts, and a little begging.

    Normally we will stretch our budget to go for internal doubles (TT2) or remote double (RR2) adjustables on our shop owned cars - which tend to be focused on Time Trial and autocross competitions. My S550 Mustang has RR2s, as does my wife's Optima entry, an LS powered 86. But MCS felt that the triple adjustables were worth it on this endurance road race car.

    The triple adjustables give us low speed Rebound, low speed Compression and high speed Compression adjustments. This is especially helpful on a Wheel to Wheel race car where "defending your line" means using a bit more curbing than you would in a TT or HPDE car. The rear shocks are setup to run as a coilover, which we normally don't do for various reasons on the E46 or especially E36 chassis BMWs.

    We got to work quickly installing these onto our E46. The front was a simple bolt-on affair with springs we had on hand. We needed that end on to be able to spec the front wheels - which we try to keep as far inboard and as close to the strut as possible.

    continued below

    Leave a comment:

  • Fair!
    Project update for March 23rd, 2020: It has been four months since my last post here and a lot has happened - with this project and "the world" in general. As I write this we're in the middle of a global pandemic, but updating this build thread will help clear my mind, and maybe give some of you something to read while stuck at home - hopefully avoiding this virus.

    This update is going to be about exactly ONE car this time: our #TeamVorshlag endurance road race car. We're trying to focus on this race car as much as possible, with the resources and time allotted to it. We have installed a roll cage, the LS V8, built the E46 M3 rear subframe, and added some carbon bodywork.

    There is a lot of progress considering we work on this one night per week with a volunteer crew. This has gone from a ratty $100 chassis to a proper race car build, with more than a few pro level drivers asking about co-drives. MCS triple adjustable dampers, 18x11" wheels, carbon bodywork, proper aero, and top level safety gear. This E46 is getting pretty serious.

    So let's jump right into this build, already in progress!


    Last time I showed our cage kit in pictures from the builder (Hanksville Hot Rods), who put it together in an E46 chassis halfway across the country. We received the kit a month after my last post, in December 2019, and we immediately got to work. This included cataloging and weighing the parts, then starting to fit everything into our chassis.

    As I write this in March we have everything installed except the door bars, and we've made a few changes and tubing additions. We're saving the door bars for last, as it is a LOT easier to wire the chassis and work in the cabin with those not in the way.

    This kit doesn't come with instructions, other than the assembly pictures that Hank sent us as he was building it. But he does mark every coped and fitted joint goes, and every tube is labeled to what it is and where it goes, as are the eight mounting plates. This makes installation pretty obvious.

    One of the main aspects that I love about Hank's design - and one that some #CageSnobs and armchair engineers might snipe about later - is where he mounts the main hoop. Instead of sticking it on the floor in front of the rear seat/fuel tank area, he puts it further back and up on a slight shelf, shown above. This places the main hoop about 6" further back than some other kits - and this is crucial.

    You have to cut a little flap of sheet metal out of the way, but the lateral structural part of the unibody here is much stronger than the thin gauge sheet metal of the floor. Also, moving it rearward makes it easier to fit drivers of varying heights, and one of our guys is 6'4", Tim Buck, and we have two 6'3" drivers as well. We need all of that room rearward for the seat to slide back, as well as room for the harness bar and shoulder straps.

    We started fitting this as soon as the rest of the interior was prepped, and the main hoop was set on the mounting plates shown in the previous steps. We tacked the plates to the cleaned and prepped floor and then the main hoop went in - it was almost touching the B-pillar, which is perfect.

    We tried to hold the main hoop then fit the forward A-pillar bars and upper windshield bar but it wasn't lining up. Turns out we need to get the angle of the main hoop set with the rear down bars, so those landing pads were burned in and those rear bars set in place.

    The forward A-pillar bars land on this bent landing pad shown above. Once we had the rear fitted it was obvious where this needed to go. Our chassis needed a little persuasion on one side and the paint stripped from both to line them up. I trimmed the corners a bit to fit a bump in the floor on the right side, then Tim cleaned the floors for welding.

    Once we had the floor adjusted to fit those front landing pads, the rest of the cage alignment got better. At this point it is mid January and we had a good bit of progress on the cage. Only about 8 hours invested at this point.

    The upper windshield bar had two bends and kicked "upwards", and was looking like it might interfere with the windshield glass. The curved "dash bar" also looked a bit challenging for use with an actual dash pad - which we wanted to use. We re-cut the cope the upper windshield bar and trimmed/lowered the A-pillar bars a fraction of an inch, and it fits below the windshield glass.

    With the main portions of the caged test fit and tack welded, the harness bar and diagonal were fitted. Then as every section was tweaked and we were happy with the fit, the tack welds were cut. These tubes then were cleaned up at each end and landing pad - the outer surface was sanded clean - then they could be TIG welded inside the car.


    In some cases the whole cage can be MIG welded - and we did MIG the landing plates to the floor pan and chassis. There is usually sealer or paint on the back side that makes TIG welding these plates difficult. Using the MIG we can burn through without issue.

    The rest of the joints and junctions were all TIG welded. Why? It comes down to heat - with the adjustable amperage control thru a foot pedal or thumb control, you can control the heat of the weld puddle, which helps control the Heat Affected Zone of the weld. If you get the weld too hot it can cause embrittlement, which is one of the reasons Chromoly tubing is no longer a good choice for road race cages and why we see low carbon 10XX series seamless tubing there (even drag racers have moved to Docal).

    On this cage Myles has done most of the TIG work, and he's been careful to keep the HAZ uniform and looking good.

    There are a lot of hours that went into prep work - you have to clean the welded area much better for TIG than MIG welding - to get the welds to look pretty.


    So the dash bar was changed from how Hank likes to make it. His tube is probably stronger, and you can stitch weld it into the cowl structure at the base of the windshield.

    The above left pic is how Hank sends the dash bar. It can be stitched to the cowl and is pretty far out of the way of everything else. But it would murder the leading edge of our OEM dash, which I demanded that we use. So we did some work (below) and made this straight dash bar instead. I will explain.

    We have a number of spare E46 dash assemblies, including this grey one and the tan one that came in this car. We took the tan dash (above right) and removed the bits we wouldn't use. It weighed in the 12-15 pound range (we will weigh it again later) but after we got a nearly finished weight under 2200 pounds (see bottom of this update) we figured we could afford a dozen pounds for a full dash skin.

    The dash mounts to a complicated structure that has a lateral bar that bolts to the A-pillar/hinge areas (see above right) and has a lot of clips and stand-offs that tie into the dash pad itself. Of course we removed the radio, computers, HVAC and other heavy bits - we just want the shell. But the easier way to mount the skin was to tie into the base of the windshield (hence the removal of the Hanksville tube) and then to keep the stock dash bar (the rusty bits above). To be able to fit this OEM dash bar in front of the A-pillar / front down bars of the cage we had to hack away at the ends for clearance, then cut the tube in half.

    Of course we could have done this intact if we had planned on using the stock dash bar before the cage was fully welded in place, but once we clearances the ends and cut it in half it could be slipped in place. Then we welded it back together. Obviously the structure of this dash bar is compromised now, with all of these changes. Hence the second straight dash bar that we added and tied into the cage. Again, it seems like a waste of tubing, but it will be MUCH easier to fit the dash skin over this straight bar than the curved bar the comes in this kit.

    Me, Tim, and Magan (our newest crew member / future driver) worked all of this out one evening, test fitting and cutting the OEM dash bar until it fit. Then the dash was almost ready to go in (above right). We'll trim the dash pad - carefully and in progressive steps - to clear the A-pillar / front down bars, and then it can mount right to the OEM structure. Extra work but it will provide proper glare protection for the digital dash we will stick inside the stock dash "nacelle", and a dash pad really makes a race car look more professionally put together. With some of the parts we added below you might understand why that's becoming more important.


    So this is where I expect some friction. On the internet "everyone is an expert" and cage analysis is something that borders on an obsession for some keyboard warriors. I've got my own personal design theories here as well, but I understand that there's more than one way to build a safe roll cage.

    This "NASCAR" door bar design that Hank does is a bit controversial, but I totally understand why he makes it this way and agree with the compromises it entails. Look, everything on a race car is a compromise - because everything depends on everything else. Moving the main hoop rearward (a damned good idea) to the point that it lines up with the back of the B-pillar makes for a tough angle to land "outward cured" door bars like this.

    This leaves a partially unsupported "S" bend in the door bars, as shown in the mock-up pics he sent us. I'm totally OK with this. And Hank happens to be the NASA Tech Steward for two NASA regions, including Texas. I'm pretty sure he'll sign off on this cage. A NASA log book will get the car into WRL, SCCA, almost any other W2W group recognizes NASA certification.

    We ordered the driver's side with this NASCAR style bar setup instead of his optional "X"or even straight bars. Why? Moving the door bar away from the driver and damn near to the skin of the door adds ROOM for the cage to deform in a big side impact. That room allows for energy to be put into the cage instead of your ARM or LEG. Having seen driver's break legs, hips, and arms with crappy door bars I will always try to do this trick.

    To avoid the "S" curve you would have to BUTCHER the B-pillar on the E46, and likely most "DIY" cage builders using a kit like his would be over their heads and they'd make a mess of it all. We did the same thing on a 4 door EVO X (above) and had to get special permission from NASA National office to alter the B-pillar. They even made a rule change in the CCR to allow this. But that was a 125 hour cage job, which was a huge money loser. I'm not keen to repeat that time consuming work on our team car.

    To save money we ordered the passenger side with the straight door bars. Plenty strong but the difference in room to the passenger is quite a bit. And with half of our team not having any wheel to wheel experience we're going to be utilizing the right seat a good bit for driver coaching before our first endurance race. So we've decided to mimic the driver's side curved bars on the passenger side (above right) - they fit with a change to the coped ends. Will show that work next time - as the door bars will go in last.


    Last time we showed this curved bumper beam but it wasn't mount to the chassis. We've finished this piece and will show the steps below.

    Getting the beam nested inside the bumper cover was part of the trick, pushing it as far forward and as wide as the E46 M3 bumper cover allows. We have zero OEM bumper structure left - this is a crash beam, clear and simple.

    Myles spent some time under the hood and working with placement of the tubular beam. Once he was happy with the placement, he and Tim made the stand-offs that were then tack welded to the flanges we cut on the CNC table (we've started making these bumper mount flanges, after a racer saw the last build update and wanted a set).

    With the beam tacked to both ends of the stand-offs it was pulled and fully TIG welded on the fab bench. I missed getting an "action shot" of this work but Myles got this welded up, even added some triangular gussets (shown below).

    I asked Myles to look at the tubular beams we've made for two other E46 models and the bracket above is a reflection of that. He made one flat mock-up that didn't work out (above right) but when he added the bends with the box and pan brake (above left) the 18 ga steel bracket really stiffened up. Adding some dimple die holes also reduced weight while firming it up even more.

    This bracket was then welded to the bumper beam and the top edge is what the top of the bumper cover sits on. We'll add a few nutserts to the bracket and some counter sunk bolts till attach the bumper cover to the bracket.

    The fully welded bumper beam was bolted to the frame stubs and is rigid enough to jack up on, add jack stands to, etc. This allows the bumper cover to finally be supported along the front edge. We'll still add two two hooks to the beam, splitter stand offs, and some brackets on the edges for the bumper cover. Will show that next time.

    continued below
    Last edited by mylesloan; 03-31-2020, 05:45 PM.

    Leave a comment:

  • Fair!
    continued from above


    We had just pulled a 5.3L LS based iron block engine from the dead carcass of my old shop truck, a 1999 GMC Sierra 1500, #TruckNorris. This truck was smashed into while I was sitting in traffic by a 1 ton van going 60 mph. Destroyed my truck, bent the frame, shoved me into a parked truck and trailer also stopped in traffic ahead of me. Don't text and drive, kids!

    That "LM7" series 5.3L is still an LS based engine, and the "706" castings are a small-valve "cathedral port" aluminum head. This article describes the 706 heads pretty well. They are probably some of the worst performing factory aluminum LS heads out there, but we can still make them work well enough to easily exceed 305 whp - and beyond. This is part of a test...

    Erik at Horsepower-Research (HPR, where I am one of the managing partners) is helping us build this car, and will co-drive in endurance races. He disassembled these heads, then we cleaned them up in the aqueous parts washer before running them for about 15 minutes in the Ultrasonic parts cleaner. The flat stone shown above right was used to knock some of the carbon deposits off the block surface, as well as check for flatness. The heads checked out great even after 273K miles of truck use. The ports still had some carbon but the CNC work will take all of that out.

    Most of the valvetrain will not be re-used, and the now bare castings have been sent off to a head porter we use for a "single pass" CNC port program. These will be assembled with steel (not titanium) valves, for our fairly modest power goal. HPR is known for BIG displacement LS engines, but these heads will be a test for an LS engine we want to develop for more economical endurance racing use.


    The intake manifold we use for cathedral port heads - along with the camshaft - will determine where in the RPM range the engine will make the most power, and can unleash more on top with aftermarket designs like the Fast or MSD. We might cut the hood later, but we wanted to stick with a low profile "car" style LS intake to start with.

    We cannot fit the taller Truck style LS intake (above left) under the hood of an E46, but they do make good power even with a smaller 75mm throttle body limitation. The 75mm mechanical throttle body versions of the LS1 and LS6 intakes are a bit snug to the E46 hood, but we made 490 whp on a 427" LS engine (above right) that was in our Alpha E36, back in 2008 - also built by Erik Koenig.

    The other low profile cathedral port intake we can use is from the LS2. These use a 90mm DBW (Drive By Wire) throttle body, which is significantly larger than the LS1 or LS6 intakes' 75mm throttle body. The LS2 DBW throttle body setup is also much "shorter" (front to back) than the later LS6 Corvette DBW TB, and the 90mm LS2 style is very cost effective, too. We have seen a good power bump by going to ever larger throttle bodies... there is almost no limit of how big you can go. 102mm is common and we've seen our 468" LS engine pick up power at 105, 108, and even 112mm throttle bodies.

    I did a bit of research on the Dorman brand of replacement LS intake manifolds and this 615-901 "LS2" model with a 90mm TB opening was a real bargain. I hadn't seen much online about this new Nylon intake offering from Dorman so I bought one and we took a closer look. It arrived and looked pretty much just like an LS2 intake. This Dorman intake is only $215.99, and its brand new. A lot of the used LS2 intakes we see for sale have cracked bosses because they are all 10-14 years old. Plastic ages...

    The Dorman 615-901 intake's casting looked pretty good except for two locations: There was a weird "protrusion" in one corner of the intake port near the cylinder head (above left), plus the throttle body opening had a lot of weird casting flaws and gaps (above right).

    I had engine builder Erik take a look and he said he could fix the flaw in each of the 8 intake ports, then we could port then epoxy the small gaps at the throttle body area. At one of our Team work nights he used a long reach porting carbide cutter and smoothed out the protrusion.

    We think this was a flaw in the internal casting dies - something shifted, and nobody bothered to fix it. Same goes for the throttle body section of the casting, where it meets the main plenum portion of the manifold. Just not a smooth transition there, lots of casting flash that had to be removed.

    The part is even made in the USA, which is weird. Maybe Dorman will have this worked out at some point - just know this LS2 unit might need some work. He was done porting the intake ports and throttle body opening in about 90 minutes, and I cleaned the intake in the parts washer at HPR later that week.


    We wanted to start with an aluminum LS block, as these are 80+ pounds lighter than the cheaper iron LS blocks. We could have sourced an aluminum 5.3L truck engine, which has a 3.780" bore. This is as small as any LS engine (4.8L is the same), and restricts the size of the intake and exhaust valves. So we looked for one of the 3.900" bore LS engines (LS1, LS6), which I happened to have. The 4.000" bore LS2 or 4.065" LS3 blocks would be even better, but those are more costly and I had a clean LS6 block I donated to the cause.

    The block was equipped with the OEM 6-bolt main caps (they are worthless without mains!) and it was mounted to an engine stand to take those off.

    Once you get the bolts out these mains are a bit tricky to remove cleanly. Erik has this custom set of main cap pullers one of his employees made years ago and I used it to pop the mains out out of the block. Each main was stamp marked before removal, of course. The thrust bearing is on the 3rd main, as shown in the middle of the block in the above left pic. The main bolts were kept but will likely be replaced with ARP studs.

    We mounted the block to Erik's mill, which he has setup for block work. The goal was to clearance this block for a 4.00" stroke crank, up from the stock 3.622" stroke crank used in the 5.3L or the 5.7L LS6. If you want to do the math, it's easy:

    ((3.900" bore ^2) x Pi / 4) x 4.000" stroke x 8 cylinders = 382.3" or 6.3L

    This extra displacement only makes the engine more reliable at the power level we are targeting - as we can make more torque at lower RPMs with the added displacement. We do this "make it bigger" trick normally to make more total power, which it does. But on any engine, more RPMs = more problems, and on an endurance engine, we can make the same power goal at lower RPMs. We ran his crank clearance program for this LS6 block and a 4.0" stroke, which takes about 45 to 60 minutes. This is to allow the connecting rod to clear the bottom of the block's cylinder casting with the additional stroke.

    Next up the block was mounted to the surfacer, and the decks were surfaced the bare minimum to make sure they were perfectly flat and square to the bore centerline. With less than .005" removed the block cleaned up perfectly. There are more steps - line hone, bearing checks cleaning - but I will show more of the shortblock work next time. And we have a second engine, an aluminum 5.3L, that we are setting up as a back-up engine as well.

    2004 330i ZHP

    Another customer tired of dealing with lots of little issues like CELs reached out to me this month and wanted to unload this Imola Red 6-speed ZHP sedan. It is out of inspection and registration, and the AC is blowing hot, so it's pretty much unsellable in Texas.

    This is a one owner Texas car, however, and it has some tasty upgrades. A 3.64 geared limited slip diff, coilover suspension he bought from us over 10 years ago, 18x9" wheels, Michelin Pilot Sports, a Setrab oil cooler, and more.

    With 162K miles, the AC system on the fritz, and these CEL issues it isn't worth a lot of money as it sits - and I don't want to fall into another "let's just find the issue and sell it" trap, as the risks of these being easy fixes are nil. We went and drove the car, however, and it is really nice. Super clean inside and out - this was owned by a BMWCCA member who cared for this car - until it became more of a burden than a joy to drive. I brought a trailer to tow it back home, since it had no plates.

    Not really sure what we are going to do with this car - we take it to lunch on nice days and it gives me bad ideas. How about a nice daily driver with a 500 whp V8? I bought this E46 M3 rear subframe (and we have a 210mm LSD M3 diff) just in case we move forward with a swap.


    That seems to be enough for this time, but we will have much more to show on the next update. We should have some progress to show on the Team Car ...

    We have a few 210mm M3 LSDs and it is cheaper to use one of these than convert the medium case 188mm E46 non-M diff. So I donated an E46 M3 rear subframe (not the same one that I bought for the ZHP) for this E46 endurance car. This has had the bushings pressed out and bead blasted - next time we will show the reinforcements we are adding and the new bushings going in.

    We will also show the sealed spherical bushing we installed in the RTAB location, which is pretty slick. Also the cage install, electric assist steering column, and more. Lots to do!

    Until next time...

    Leave a comment:

  • Fair!
    continued from above


    I teased this last time, and I'm not going to share everything now - because this brake kit is currently untested. We could have just bolted on E46 330 brakes, which are an 1" larger in diameter from the base 325/318/328 brakes, as shown below. We've done this cheap upgrade on a number of 325/328 cars before. But this car is going to be in WRL GTO class (more on that below), with V8 power and 315mm tires... it needs MORE BRAKES.

    We started developing this swap kit last June and tested 6 different rotors and a few calipers. I bought a number of rotors, including the E46 M3 325x28mm, the ZCP competition M3 2-piece rotor which is 345x28mm (and $$$), and some other rotors. We mocked up the Powerbrake caliper on a number of these but the prices start ti get extreme if we use that caliper.

    We kept coming back to a particular Brembo 4-piston caliper, which we have a lot of experience with. This is not a radial mount Brembo like the Porsche calipers some BBKs are based on. Those Porsche calipers need to be machined and still require a somewhat expensive caliper + core to work.

    We attempted to use this with the E46 M3 rotors but the spacing for the Brembo, but with the somewhat "small" diameter 12.8" E46 M3 rotor, the spindle mount spacing just didn't work well for this caliper's mounts. And honestly we wanted a bigger rotor for endurance racing - which is where we see this kit working well, as the E46 is a popular endurance race car chassis. We actually made a bracket to where this Brembo to this M3 rotor but the caliper had to scoot "up" enough that part of the pad sat above the rotor. That's going to make the pads wear poorly so we abandoned this M3 rotor. Shame.

    Next we tested a number of larger non-BMW rotors with the same 5x120mm bolt patterns, including this 1-piece 13.6" (345mm) above left and a 1-piece 14.0" (355mm) rotor above right. Even though we would be going to an 18" diameter wheel for our car, we knew many endurance E46 racers wanted to stick with 17" wheels, so we used our 17x10" Forgestar as the "go / no go" gauge for our brake fitment testing. We even tried a 14.5" rotor but it was too tight for safe use inside this 17" wheel.

    The best fit for the 4 piston Brembo caliper on the E46 non-M spindle was on the 14.0" diameter rotor (355mm x 32mm), which is a monster. It had the right bolt pattern but we had to slightly re-machine the opening to fit over the BMW hub. Myles used our CNC lathe to make this cut and it worked perfectly. This rotor weighed 24.0 pounds before we machined the hub and chamfer. Very cost effective.

    I am not showing our E46 mounting bracket just yet - we made prototype brackets that bolt-on without mods, but they aren't production quality looking yet. Once we get some laps on this brake setup, and if they work as well as they should, we will sell this as a kit (rotor, caliper, bracket and hose). Gives us BIG brakes, affordable calipers and rotors, with a massive pad selection. Fits within some 17" and all 18" wheels. Stay tuned for more.


    I teased this last time as the widebody kit had just arrived but we hadn't mocked it up well yet. We needed the bumper cover, left door, a wheel and suspension, and the correct left fender mounted to test flares these completely. All of those other other steps have been completed so now we could finally test fit these bits properly at all 4 corners.

    We were excited to try a widebody kit that we could buy for so little. This looked good for both clearance and minimal drag. The aero of a fender or flare matters, especially when you are bombing down the back straight at COTA going 150+ mph. We found out later that the images used by Duraflex on their website are only 3D renderings, and even those are from a competitor.

    We got the kit that we ordered (we are a dealer) and the fit and finish was pretty good - we have used a number of items from this brand and quality can be a bit "all over the place", but this was one of the better fitting setups. We spent several weeks rounding up a LF fender, mounting the nose and hood, getting the driver's door on, and mounting the suspension/wheel/tire/brakes - before we could mock these up properly.

    These are made to work with the M3 nose and M3 lower skirts, so we had a gap at the bottom where the skirt was supposed to be. But we have some M3 skirts laying around, that won't be a big issue. The fronts and rears both fit surprisingly well. The rear had plenty of tire clearance...

    ...but the front will only clear a 275mm tire. That's the problem with looking at the drift or stance communities for flare options - they never run a lot of actual tire WIDTH, just going for the stance or a tire that makes lots of smoke.


    These flares won't fit over our 18x11" wheels up front, but for a racer or team running a 275mm tire on a 10" wheel, this should be ideal. Interested? We'd sell this whole kit at a loss for $400 shipped - call us at the shop if you want this set. Only mocked up, never drilled or bolted on.


    Many of you know that Vorshlag is known for making higher end roll cages in road race cars. But if you have read this post titled "we make roll cages" you might realize that our cages cost a bit of money. Because they take a long time to plan, prep, bend, notch, fit, and weld. 60-75 hours is normal for a car like this.

    Spending 75 hours building a cage from scratch - after hours and in our free time - could takes several months to complete. We tried to shortcut this time by ordering a "cage kit" from a reputable shop known for perfect fitting BMW cages. These are pictures of the kit built for our car, remotely, using another E46 coupe chassis to build within.

    Back in May the team voted on this option, and then paid for this E46 kit from Hanksville Hot rods. They build their kits inside the same chassis as you ordered - but it took longer than expected to round up an E46 coupe to use. And longer still to complete the kit. Stuff happens.

    This was an experiment to see how many hours we could save by ordering a kit and just doing the final welding here. It likely will save a 40+ hours of fab time, once it is complete and in the car, but our 6 month wait to get the kit built did nothing beneficial for our build's timeline. We had hoped to be on track in the Fall of 2019 but we are now pushing into Spring of 2020. We will show more of this kit being installed into our chassis next time, then many things staged behind this will follow.


    After the Duraflex kit proved to be too small up front for us we immediately started looking for an option that could clear our 18x11" wheel and 315/30/18 tire we will be using. Since 2017 "Clinched" has been making some stancey widebody kits and flares. They make a series of "universal" flares from thermo-plastic, which are formed on a vacuum table - a technique which we have used in the past.

    We had started to see these show up on legit road race and autocross cars with BIG wheels. A buddy had purchased a set of their "Euro" style flares with 100mm (4") widths. They worked to clear a 335mm tire on his Subaru track car (below left) and the same units on this CTS-V road race car looked pretty good. This style is made to be trimmed to fit, then bolted on.

    We borrowed this 100mm Euro flare and mocked it up on both ends of our E46 coupe. They have more room than the front Duraflex widebody kit.

    This won't be as clean of an install as the E46 specific widebody kit, but it will give us full coverage on the protruding part of each tire, and we can vent behind each tire by trimming the flares short on the back side. We became a Clinched dealer a month ago and ordered a set of flares this week for use on this car. We will show that installation work in a future post.


    We have been staying quiet about the engine, but it's Vorshlag - what did you think we'd build? Of course an LS swap is in order for our E46! Look how good an LS V8 fits under the hood of an E46...

    An old prototype set of our stainless long tubes was rounded up, we built some mounts, have a brand new transmission which we will test (which I cannot talk about yet), have an E46 M3 rear subframe and diff to use, and more.

    Once we agreed upon the class we wanted to run (GTO) then the engine we would use became obvious - an LS V8 engine.

    Even running the highest class in WRL (GTO) we are still limited to a fairly tame 9 pound per whp. And unlike NASA ST/TT classes, they calculate with no driver (but full of fuel). We need to know what the car will weigh then figure out how much power we can make...

    We haven't done a W2W prepped E46 LS build yet, but we did build a caged E36 with a 427" LS engine and T56 Magnum before. This was our "Alpha" E36 LS build, which we raced from 2006 to 2009. Fully caged, with a fire system, aluminum LS, full exhaust, oil cooler, big radiator, Accusump, heavy 17x11" CCWs, all of the factory glass except the doors (which were gutted), and a single racing seat it tipped the scales at 2508 pounds, without fuel. The E46 chassis is a little bit heavier, plus it will have full aero + driver cooling system - so lets call it 2750 pounds full of fuel and race ready.

    2750 lbs / 9.0 = 305 whp

    This peak number of just over 300 makes a BMW M54 based engine out of the question. And yes, we could have built a higher strung S54 E46 M3 engine for this car, those aren't exactly inexpensive or known for massive reliability in endurance racing. Costs for an LS are much lower for us, and we are known for LS powered BMWs, which pushed us to an aluminum LS. We could make this with the smallest displacement 4.8L truck engine, or easily with a stock 5.3L. But we are going to "overshoot" our power goals, then dial it back with a using a custom "flat tune" by way of a factory Drive By Wire (DBW) throttle body. You could do the same thing with a physical restrictor in front of the throttle body, too.

    continued below

    Leave a comment:

  • Fair!
    Project update for November 29th, 2019: Another long gap since I updated this thread, but we have been pretty busy working on several E46 cars in the shop.

    This time we have three E46 chassis we are going to touch on. The first is my black 2003 325Ci that has been around for two years but was recently sold. The next is our Team Endurance build, the E46 coupe shown above. There has been a lot going on behind the scenes since my July update - as well as a significant delay that was out of our control.

    Lastly we will talk about this gorgeous Imola red ZHP 6-spd 330 sedan above, which I bought from a customer recently. It has some little issues and CELs that won't be easy to fix. Our plans with this car have been effected by how hard the black 325 was to restore and sell. So let's catch up!

    2003 BMW 325Ci SOLD

    I bought this clean E46 coupe automatic from a customer in May 2017 - a car we had worked on for him in the past, but when we moved our shop he started going elsewhere for repairs.

    After a few "random" repair shops milked a lot of repair jobs from him over a few years, it got too expensive to drive and for him to maintain in a perfectly functional, super clean form. This is the fate of many E46 models in 2019 - they have aged a bit now, can become plagued with electrical and sensor issues, inevitably they get some problem that throws a CEL (Check Engine Light), and other lights on the dash start to freak people out.

    This car was handed down to one of his college age kids, which did the 325 no favors. It got a bent wheel and delayed maintenance until it just stopped running at one point. I bought it for a good price but if you read the extensive repairs we have detailed here you know I had a lot of time and money in this car. All of the suspension, lots of underhood repairs, the tires and brakes, interior updates, swapped the transmission, etc. It had a CEL that we kept chasing, and I finally threw my hands up.

    This car was never going to be a good candidate for a race car build, as it was a 325 with a slush box. The AC worked but with a CEL it was virtually unsellable. We cleaned it up extremely well, posted some really nice pics and details on Craigsligt then FB Marketplace... all we got was tire kickers and trash pickers. $1000 and $1500 offers, sight unseen - we never even had one person show up to look at and drive it. Sad.

    The car was super clean, and drives great. One of my employees needed a daily so I sold it to him cheap, and lost a bundle on this. But my wife drove it for about a year, so I have to just look at that as "the cost of driving a car". Moral of the story here is: don't buy that "cheap E46" you see for sale, thinking you can fix it up and flip it. This was a 100% Texas car (rust free), straight, super clean inside and out, had D-Force 17x8.5" wheels plus great tires... but with 151K miles and a CEL it was hard to sell. It was sold for half what I had in it. Lesson learned.


    Of course this car's HVAC blower motor quit working almost immediately after he bought it, so we fixed that on my dime. Blower motor & blower resister are both a "high failure item". There are detailed links below on both tasks:Since I was already selling the car at a loss, we tried the less expensive part that potentially had more labor hours first - the resistor.

    You can access this behind the glove box, and this trick saved some Brad a lot of time on this task. After about 90 minutes the resistor was replaced and the fan immediately started to work, and has worked ever since.


    This should be an easy one, but I re-learned a lesson here. The left front fender was smashed when we got this rolling chassis for a song - not a big deal, as I keep a couple of pairs of front E46 steel fenders in stock to use for metal flare jobs on E36 chassis (from before - when there were not good flare options). But it had been a number of years since I had bought these fenders...

    Again, we haven't done a steel E36 flare job like this in years - because there are so many good flares and widebody options for the E36 now. The E46 is no different, as I will show below. But I had forgotten that we utilized E46 non-M SEDAN front fenders for our E36 flare jobs. It came down to the recessed trim section in the sedan fenders was further back and "out of the flare" section. That made the welded steel flare jobs on E36 cars easier. We would cut out the fender flare portion of these E46 fenders then graft them to the E36 (see above right). It was a bunch of work but could turn out nice with a little bodywork and paint.

    So when the smashed coupe fender was removed, I grabbed one of these SEDAN fenders, not remembering it wasn't a COUPE front fender. It was on the car for a couple of months - because with the front nose and left side door off it wasn't obvious it was the wrong one. If you look at this fender installed, above right, you will notice the body lines from the A-pillar don't match up - that's all that was visible... So when we test fit the Extreme Dimensions flares (shown further below) it "didn't fit".

    Again - a weird mistake, and it would have been immediately evident if the door was installed. Luckily replacement coupe fenders are still cheap for these cars and I found some for $58 shipped. I used to pay closer to $33 for these import fenders from a local Certifit store, but that's a 3 hour round trip in traffic to save maybe $20. This is one of the few things eBay is good for - cheap used parts or import body parts. Probably won't be the last fender we will need on an endurance car, hehe.


    We aren't 100% done with this step but I will show some progress. The "M3 style" front bumper cover is an import unit designed for use on a Non-M coupe chassis. This is often used by Spec E46 users, and we will utilize this item for the better grill openings and flatter bottom - which makes adding a splitter easier.

    At this point we have the bumper cover mocked up - we needed that for the flare fitment tests. The factory plastic brackets at the tub are holding the receiving "cups" on the bumper cover, with the weight held up by a bucket for now. The cover needs a bumper beam to mount to, with brackets to hold it in place. We plan to have a rolled radiator that is feeding the radiator from the lower grill opening only. to make room for that a tubular bumper beam is a trick we often use to make more room. Here's an example of what we have planned, which we built this year for my wife's LS swapped 86...


    We almost always start with our tubing roller (below left), install the appropriate dies, and then pick a piece of 1.50 x .095" wall, 1.75" x .095" wall or 1.75 x .120" wall seamless DOM tubing. We cut this to length and then bend the main curve to match the bumper cover.

    On this car we were using a carbon fiber aftermarket nose, which had both a curve and needed two bends to kick in for the portions outside of the radiator. Some folks will stop their tubular bash bar at the frame rails, like most OEM beams do. We have seen car-to-car contact rip bumper covers off, destroy headlights, and more. With our full width bumper beams on other cars we have seen our customers "come out on top" of any contact.

    Above left you can see how closely this tubular bumper beam matches the shape of the nose we are using - again, necessitating a couple of bends to kick in outside of the frame rails and under the headlights. This FULL WIDTH beam is much stronger and protective than the "half bumpers" we see some build. The mounting plates are cut on our CNC plasma table then the bar is mocked up underneath the bumper cover to figure out the lengths for the tubing mounts. These are fish mouthed and added to the mounting plates and beam. It is all tacked up on the car but finish TIG welded on the fab bench, above right.

    These pictures above show the rolled radiator - its also only fed from the lower grill opening, and mounted way forward and down. This makes venting the hood much more effective, and we will do the same thing on our E46. The upper and lower radiator mounts will be custom made, of course. We may or may not make a duct box to the hood opening behind the radiator, but we will definitely make the lower grill opening ducted to the front side of the radiator and oil cooler.

    This is as far as we've gotten. On our next weekly work night we should have this tubular beam welded to the mounting plates at the frame stubs, visible behind the bumper in the pic above. Then we will add twin tow hooks to the font, some simple brackets from the tube to the bumper cover, spec the radiator, and build brackets for the radiator and oil cooler. Much more on this task next time.


    We bought this car on very worn OEM struts, springs and "mushroomed" top mounts. After some initial work on one of our 2-post lifts this car was moved to a back corner of the shop for the next phase of work, and the OEM struts were tossed. They were total junk. We needed wheels on the car to test fit the fender flares and for our design work on the Brembo BBK, but the OEM stuff was so long that the ride heights would be totally wack.

    Luckily we had an extra Ohlins E46 coilover strut so we found a coilover spring, added a Vorshlag camber plate, and mounted that to the left front. This is not likely our final suspension but close enough for mock-up testing.

    One small downside to inverted struts is the spring and body lengths make it harder to fit "the spring above the tire", which limits how far inboard the wheel can fit. Not an issue with most wheel setups on these cars but "We're going to eleven". We need ALL of that room and more. We mounted one of my E46 17x10" Forgestar wheels and 10.2" wide Hoosiers for the next steps.


    In my last post I showed how we got the doors down to 29.0 pounds with some serious cutting, gutting, and removal of the window glass and associated mechanisms. We used a variety of cutting tools to get this structure out - including the plasma cutter and some cut off wheels in a pneumatic die grinder. Both methods are loud, noisy, and messy. Plasma cutter is probably the worst way to do this work, as it leaves a super rough edge that we then had to grind or cut away.

    We foolishly forgot to weigh the full weight doors with glass so I don't have a good starting point to reference - but this 29.0 pound weight still seemed heavy for a gutted door, to me. Something didn't "feel" right about that weight. A buddy of mine (Andy) owns Clownshoe Motorsports and said his doors were lighter, so I stopped by their shop one Saturday.

    I can't show many of the endurance racing secrets he shared with me that day, but we did measure some various tires, and noted the technique he uses to gut doors. They leave more of the upper structure but remove ALL of the lower structure, and much of the door striker bits. So we took our 29.0 pound doors and went to town on our next work night.

    Tim and Jason got to work with the Saws-all and it proved to be a more efficient, less messy tool for cutting the door structures. Leaves a much cleaner edge, too. We cut off the ugly edge left by the plasma cutter and then started to work on the metal below the latch plate.

    I then used some extreme care with the cut off wheel and took the upper "crash structure" out at the top of the door, on the inside. The slotted, 3D shape shown in the picture above left. We took this out of the passenger door, and it is heavy. All told we found another 2.1 pounds, which isn't a lot. We had already taken the main crash beam, glass, and regulator out of the door. We were starting to hit a big "diminishing return" type of task.

    Tim suggested we KEEP the upper structure on the driver's door (shown with a red box around it, above left). He crews for two different pro level road race teams that have driver changes, and he has noticed that they tend to lean on the upper part of the door during stops. So we left that in the left door, and it is only 1.1 pounds heavier at 28.0 lbs (above left). This door was weighed after cutting some of the inner structure out and with the window + regulator removed, but the diagonal "crash beam" in place at 34.7 pounds (above right).

    I made sure we weighed the full weight door (above right) on our 2015 Mustang road race project, which is going on a SERIOUS diet and getting an LS swap. 84.2 pounds for a door is extreme, but keep that in mind when you are gutting your door. We might find another pound in these BMW doors, but we have kept structure at the hinges, striker latch, side mirror mount and along the top of the driver's door. Any additional weight removed is going to make the remaining door compromised... I think we are there.

    continued below

    Leave a comment: