Announcement

**Fair!** · 11-04-2024, 04:14 PM

continued from above

ENGINE FIRES UP!

July 16th the engine ran for the first time in at least 7 years after just 6 days of work. That was a big step! This was after replacing the fuel pump and filter and adding fresh fuel only. But it ran pretty rough, clearly had some vacuum leaks (many vacuum lines had been replaced already), and we had more work to do.

A couple of weeks later on July 30th, having made made progress on other systems, it was time to try more outside running tests again - so a can of Seafoam was inserted into the intake tract and it was run like this for about 10 minutes. This stuff is a heavy duty top end and injector cleaner, and while it did spit out some smoke for a bit, it ran no better. Then while idling on the SeaFoam, the alternator "released the magic smoke"....

The magic smoke only comes out of electric components once! Christian pulled the alternator and found all sorts of bugs and grass behind the cooling duct. The brush assembly was removed and they were both HEAVILY worn, and the grass and junk had shorted something inside. So I went onto RockAuto to ordered the brand new (not rebuilt) replacement. I was very careful about which brand and model I picked, too.

A new one showed up in a box a few days later that someone had played "Rico Swappe" with, and it was absolutely the wrong unit - but in a box with the right part number. This made for a two week delay fighting with RA for the return and replacement (they don't have customer service reps that answer any phone number), but after some back and forth with a bot, the right unit finally showed up August 12th. that went in, and the car ran fine again. Well, it ran "like it did before", which was still plagued with vacuum leaks and a cylinder miss. More on that next time!

VARIOUS BEAUTIFICATION TASKS

The general nattiness of this car really did bother me, so I spent a few bucks on some front end bits to pretty things up a bit. New headlights, upper grills, fog lights, brake cooling ducting, and even found a black lower grill to replace the red unit (which was OEM in 1995, but I just didn't care for it).

A good bit of elbow grease went into removing the flaking clear coat and polishing some areas of the paint. We still have a lot of work to do, but it was finally looking a bit better by the end of July.

The interior looked about what you would expect of a somewhat neglected 30 year old car that had sat in the Texas sun for far too long - the leather was pretty rough, the glove box door had fallen off, and the door panels were coming apart. But it wasn't stinky or wet, so it was mostly salvageable. The glove box door was epoxied back in place with a little bracing to hold it in place for 24 hours, as shown above.

The trunk was full of junk but once cleared out we noticed this huge subwoofer box, CD changer, and massive amp. The speakers were fried but the amp was a popular vintage unit that I traded away - for another car!

I was displeased to learn that these OEM wheels were all 17x7.5" at all 4 corners, so those were pretty much useless. I would never be caught DEAD running wheels this narrow on an E36 M3! So I borrowed a buddies vintage CCW 3-piece 18x10" wheel, cleaned that up, and used it for some wheel testing.

We WILL run something at least this wide and even flashier once we get the upgraded suspension on the car. The "teaser" pics at the top of this post show some MOMO 18x9.5" wheels (above left) on the car for our first track test, but those are very temporary.

OEM BRAKE UPDATES

We always like to move to motorsport brake calipers and rotors when the class rules and budget allows, but until this car proves itself worthy of that level of spending, I decided to order some inexpensive OEM style M3 coated brake rotors and some cheap brake pads. This way we can do some "baseline" track testing with some new pads, rotors and fluid. We also replaced the front wheel hubs, as they were worn, but the rears checked out fine.

While we had the front hubs off the car, I asked Christian to work on his first brake cooling deflector prototype for this E36 chassis. There is an elaborate "dust shield" on these cars that covers the hub and back of the rotor, but with the hub off it can be removed and modified for better cooling.

We could have just left this whole thing off, but it does keep dust and debris away from the hub and wheel speed sensor, so we chopped it down to what you see above left. Then the brake cooling deflector was made using cardboard and a couple of prototypes until Jason and I liked what we saw.

With this deflector on the front corners the air from the now replaced factory brake cooling ducts can finally get to the inside hat area of the front rotors. That makes the factory brake cooling inlet ducts FUNCTIONAL and will extend the life of the brake pads, rotors, and wheel hubs.

During any track stint these deflectors keep the brakes cooler for longer. We've tested this style of brake cooling on about 8 chassis now and it ALWAYS works. The first track test in this car was enough for me to decide to move this into production. The top right image is an earlier prototype, but the second prototype version allows for more cooling air to get to the hub and hat area.

We couldn't install new rotors, pads and fluid without addressing the 30 year old, rotten rubber brake flex lines. All six of those were replaced with Stoptech stainless braided hoses.

One of the rear brake hard lines was rusted and stuck, and the fitting rounded off when removing it, so a new line was replaced. Just "old car problems", even for a Texas car that has never seen salted roads once. Motul RBF600 fluid was bled through the system before our first track outing.

OLD SUSPENSION PARTS REPLACED

We had just started in on the front suspension inspections when it was obvious that the front control arms' ball joints & bushings were worn, and tie rods were as well. I hunted around for replacements from Leforder or Mayhle HD and... well those are not longer available from my old sources for an E36 without spending BIG money. FCP Euro had some name brand versions, but they were 3x more than I remembered paying in the past.

So I did what i don't like doing and bought some off brand versions from eBay and Amazon. Yes, it was a cringe moment but I wasn't still sure how far we would take this car down the Racecar build. I just needed something that wasn't totally trashed and good enough to get through a few track tests before we got to more a serious suspension on the car.

These off brand arms and tie rods were installed with new tie rod boots and they fit great, and we have been using them for a while. We also added Powerflex bushings to the LCA, but I will talk more about that next time. In the image above you can see the opening between the brake deflector and the front rotor hat - that's actually enough to do some real good.

INITIAL PLANS + WHATS NEXT?

I wanted to just post the first few weeks of work on this car, and stopping here after we got it running and the alternator replaced on July 30th of 2024 is a good stopping point. But let's discuss what we have planned and some of the highlights of what you will see in future posts.

Once we realized the engine was good I went hog wild and fired the parts cannon again and again. We have MCS RR2 remote doubles for the car, a full cooling system replacement "essentials kit" from Mishimoto, and the entire catalog of Powerflex bushings for this car.

We also went a bit overboard on the rear suspension and did a full rebuild of all bushings, SPL lower arms and spherical bushings, bead blasted the diff cover, and cleaned everything out back. An oil pan baffle kit and oil pump drive upgrade from Achilles Motorsports was installed and all new gaskets went on the engine, curing all of the oil leaks.

Then we attacked the interior with new E36 seat bracket development, Sparco EVO XL seats, a MOMO steering wheel and NRG quick release, and a modified 4-point roll bar with new Sparco harnesses. We also cleaned up a lot of things under the hood while replacing and repairing various parts - and now just in late October the engine is running on all 6 cylinders reliably.

We are about to order a set of widebody over fenders, Apex 18x11" wheels, and a full Max4 aero package. So stay tuned for the next installment when we will show more of this on Project Hellrotten! You can see real time updates on our Vorshlag FB or Instagram pages (look for the #Hellrotten hash brown).

Thanks for reading,

Terry @ Vorshlag

**Fair!** · 12-26-2024, 06:20 PM

Project Update - Dec 26, 2024: The last year (2024) has really flown by, and we have worked on 9 different Vorshlag owned project cars - our 2018 Mustang we call Trigger, which we raced all year and even took to SCCA TT Nationals. Our 2024 Mustang Darkhorse which Amy raced all season in Texas Region SCCA, then sold in November. A 1988 Mustang which we semi-restored before it goes for its first track test, as well as a 1989 Camaro IROC-Z which got restoration, some upgrades, and its first track test.

We also bought back an E30 (1991 BMW 318is) that we sold 16 years ago - we purchased this to "rescue" it, and it has received a lot of the same "restoration + race prep" work as the E36. There was an E46 ZHP that got a ton of attention, and my '22 Maverick and Amy's '23 Bronco, among other vehicles. Last but not least was our red 1995 M3 Project #Hellrotten here - which we have now tracked twice and done a ton of restoration and upgrades to!

Long story short - it was beyond a busy year for our little race shop to maintain and upgrade these shop vehicles + customer cars, but I wanted to sneak in one more Forum Build Thread update before the end of the year, and we picked this E36 project to cover. Much of the work shown below happened from late July to late November 2024. Let's get to it!

FULL POWERFLEX BUSHING INSTALL

With any 30 year old car that has been stored outside for much of its life, you have to look closely at ALL of the rubber and plastic on the inside and out. The rubber suspension bushings on this M3 were looking pretty old and craggy, so we made the decision to order the entire Powerflex catalog of bushings in their "Black Series", which is their racier / harder durometer versions.

The most damaged bushing on the car - and one of the most critical bushings to improving handling - was the front lower control arm rear bushing (LCA). These are super soft from the factory and very hard to remove from a control arm without destroying.

Last time when we showed the new LCA going on the bushings came apart. We have to salvage the steel "lollipop" housing, which we did, and have now pressed in the new 2-piece polyurethane Powerflex offset version. This is one of the few bushings on the BMW that has to pivot in 2 axis - which stiff poly does NOT do well. So Powerflex makes this a 2-piece bushing, with one bushing that rotates within another, and that allows just enough pivoting to keep from adding bind in the suspension.

We kept the 1992-1995 "offset" LCA bushing design and matching arms to go with our 1995 M3 here. The 1996-99 models use a "centered" bushing and add caster in another place. Of course we drilled the lollipop and tapped it for a grease zerk, with a hole in the outer bushing to allow grease to pass into the inner bushing interface. Annual greasing of this zerk will keep these poly bushing working quietly and smooth for ages. I will show the other Powerflex bushing installs for the rear in a section below.

MOOG SEALED SPHERICAL IN RTAB

The Rear Trailing Arm Bushing is another "2 axis of rotation" bushing on the BMW, and as such needs to be able to both rotate and pivot on a different plane. This is where we always avoid a stiff poly bushing, and either use a Lemforder Z4M rubber OEM bushing and our RTAB limiters or this Moog "problem solver" sealed spherical bushing.

This is a bushing we have installed on E36 and E46 models before, and it pivots smoothly because it is a p[roper spherical bearing. But it is also SEALED from the elements, so it doesn't get blasted with rain / grit / salt like a racing style "all hanging out there" metal spherical does. The inner bore of the RTAB arm housings or the outer diameter of these Moog units need to be shaved about .002-.008" to get a proper press fit (.002" of interference), and I am not going to try to show this here - because I don't need a bunch of PMs or calls from folks for a product we don't sell...

I will show that the RTAB cassette needs to be drilled out from an M12 hole to a larger M14, and the bolt has to be upsized as well - to mate to the Moog unit. The cassette also needs to be spread out just a hair, but otherwise it is a relatively smooth install. There are other forum posts and YouTube videos showing this work.

NEW VORSHLAG RTAB POCKET REINFORCEMENT

We have made a weld-in RTAB pocket reinforcement for the E46 chassis for a while now and realized on this car that we never made the E36 version. So we made a "rubbing" of the factory RTAB pocket, scanned that, turned it into a CAD drawing, then CNC cut a pair of these. After a few small revisions we had a production worthy part, and the guys got to work cleaning up and welding them into the chassis.

Again, this was a Texas car so it wasn't "rusty", but it sat outside for a lot of years so they needed a little clean up. The RTAB cassettes were bead blasted and repainted, as they looked a little crusty.

The chassis side of this RTAB mounting was cleaned up and paint was removed around the perimeter of the plate we were to weld in. The revised E36 RTAB reinforcement plate was mocked up, then tack weld each plate in place.

We like to use a TIG with a special rod to attach anything that needs to be welded to a BMW chassis, as we can better control the heat and prevent blowing holes in the chassis. We had the interior out of the car in the back seat area and a "fireman" in the back seat area with a spray bottle of water, in case there were flare ups of materials. Once we have the full perimeter and around each bolt hole welded, we slather everything in seam sealer.

The next day we hit everything with Zinc based primer made for bare steel. You can then cover that with something "pretty" and some color, but for now that worked for us. We're not going for a concours restoration here... at least I keep telling myself that!

REAR SUBFRAME & DIFF HOUSING RESTORATION

This is where I kinda pushed things over the edge and we massively detailed everything on the rear subframe... I just really hate janky looking suspension parts, so I helped clean things up and pushed Christian to do the same.

The cleaned up finished subframe assembly, above, is probably too clean for this car, but it makes me happy when I see it. Christian pulled the whole assembly out of the M3 on July 31st, 2024. We power washed it outside and I got covered in grease, but that's part of the job. I then used my secret WD40 cleaning techniques and got the subframe and arms all shined up.

As you can see above right, all of the stock bushings were swapped for the Powerflex poly units in the subframe. That took some effort with our mega-sized C-clamp tool, sometimes some heat, and a bit of persuasion.

The stock RTABs fought pretty hard, as did some other hardware. We took the rear diff cover off to inspect the Limited Slip differential and gears, which all looked great. That was all cleaned up before it went back together.

I cannot stand rusty bits on my race cars, so the 188mm "medium case" LSD housing was removed. It was then cleaned up, degreased, taped off and painted gloss black with 3 coats of paint over about 48 hours.

I bead blasted the aluminum diff cover a few times until the crust and grime was all gone. That leaves it in a "raw" aluminum state, and it needs to be finished with something. Instead of waiting on the time it takes to clear anodize aluminum I found a suitable "ceramic silver" engine paint and gave it a few light coats over a couple of days...

The new Powerflex bushings were pressed into the 3 points on the diff housing and cover, and I even painted the cover bolts, speed sensor housing, and Christian got it all put together. Then the diff housing was reinstalled into the subframe as the work wrapped up about a week later. It all looked SO GOOD when it was finished.

SPL PARTS REAR ARMS & SPHERICAL BUSHINGS

There were a couple of other small upgrades out back we wanted to tackle - and SPL Parts had what we needed. The upper bushings at the rear uprights were cruddy and those got replaced with their spherical bushing kit.

These lateral lower arms on BMW E36 and E46 models are interchangeable, and we often see the factory stamped steel arms bent - mostly from tow truck drivers stupidly hooking chains to these during a roll back tow. The SPL Parts version is a more adjustable tubular design with a spherical at one end.

On the opposite end, the outer bushing can be replaced with another SPL Parts spherical housing, as shown above. This includes a knurled housing that is pressed into the steel upright and then a spherical bearing inside, with compliance bushings to make up the distance at the forked end of the mating arm.

We have installed these to numerous E36 and E46 model cars here at Vorshlag, and we will do this whenever the rules allow us to replace the stock arms.

The image below is the entire E36 rear subframe assembly (shown upside-down) on the bench, fully upgraded and restored, about to go back into the M3.

This took probably 3 full days of work to get to this point, but well worth it. After track testing we noticed zero issues with clunks, looseness, or weird handling.

SUNROOF "DELETE"

This is one of those common things done to a race car but there are good reasons for it. First is the weight - we replaced this 36 pound sunroof cassette with a 2 pound panel (later), and that 34 pounds net removal is from the very top of the car. We will reinstall the headliner at a later date, to be SCCA TT Max class legal - more on that next time.

We also gain much needed headroom - for me (bottom left) that is welcomed. For Amy (bottom right) that is not at all needed, ha! We are working on some tweaks to the lower seat cushion in the Sparco EVO seats to better fit both of us - more on that in a future installment.

We ran both track tests #1 and #2 without a panel in place, and the open roof panel caused some real issues - I will cover that in the Track Test #1 review, below.

FULL MISHIMOTO COOLING UPGRADE

This brand is very polarizing to some readers, and I get it. It is a Japanese sounding name for an American company who clearly builds much of their stuff in Taiwan. They have a lifetime warranty and we have had exceptionally good results from the brand, but others blame everything from cracked cores to global warming on thm. If you don't like Mishimoto then choose CSF or one of the many other import aluminum racing radiator brands.

For this 30 year old car with much deferred maintenance, I was wanting to change EVERYTHING in the cooling system at once - water pump, radiator, coolant expansion tank, hoses, thermostat, electric fan upgrade, and more. We went with this package "Essentials bundle" that included much of what we needed.

In addition to the thicker all aluminum radiator this bundle includes the electric fan conversion kit, shown above left. It comes with all of the mounts, wires, mounting, and relays needed to ditch the problematic and power robbing mechanical cooling fan. The bundle also includes the all aluminum coolant expansion tank, which replaces a plastic unit that often cracks and fails.

In the 2nd week of August, Christian tore down all of the cooling system upgrades and knocked this out in about a day of work.

PART RESTORATION, PART RACE CAR BUILD

Any time we are working with a car that is 30 years old that has seen a lot of neglect, we have to restore many things that we take for granted on relatively new race car builds.

The driver's side window motor is a common failure point and this car had a dead window from the time we bought it. RockAuto to the rescue!

As shown in images above, we started with removing the door panel - which was trashed. Then you have to drill out some rivets to swap over the new motor and rivet that new part in place.

The door panels are falling apart so we will work on a lightweight plastic replacement at a later date. The lower windshield cowl panel plastics were crumbling but I ordered this replacement from Schmiedmann in Denmark with a big parts order (even with shipping from Europe, this was cheaper than US based shops - at least for some parts and bigger orders), and it looks great when replaced.

continued below

**Fair!** · 12-26-2024, 06:30 PM

continued from above

NEW VORSHLAG SEAT BRACKET BASE + SEATS

This work spanned several weeks and took a few design revisions before I was happy, but the end result is now we have seat bracket bases for the E36 chassis - a new, possibly better way to mount racing seats into this chassis. For this dual purpose street/track car we are adding fixed back racing seats but with a slider (for multiple drivers) and both the OEM retracting 3-point belts as well as 6-point Sparco racing harnesses.

Picked up the 4 seats above in an annual Sparco sale, with the two fixed back EVO L models going into our E36 and the two tilt back Sparcos going into our little E30. I also bought some steering wheels, sliders, and steering wheel Quick Release (QR) units for both cars.

On August 16th, 2024 we started on this E36 seat install by pulling the driver's seat and making a cardboard template of the factory holes. We're making this seat base bracket to work with the factory carpet and wiring underneath (we have to keep carpet in SCCA TT Max class), but it will work in a stripped race car as well.

We then tied a string and weight to the center of the steering wheel, and marked that centerline on the seat base - you can see how far offset the factory seat bolts are to the wheel! We mean to correct that in our design.

The cardboard template that Christian started with was mocked up with the Sparco EVO L seat and Sparco sliders, all connected with our Vorshlag side brackets. We modified the template several times and left room to allow the driver's side seat to slide to the right, to better line up with the steering column (see the string). We weighed the stock seats (above right) while they were out, too.

Myles drew up and CNC cut this early prototype plate. One thing we came up with to be able to use these brackets as low as possible but still clear carpet and wiring underneath were some cylindrical risers turned on the manual DRO lathe. Those will be CNC machined for production, and welded flush to the top surface (to let the sliders sit on top of those spots, if needed) - this new idea will come in handy on a few other seat bracket designs we have in process, so that pretty big breakthrough!

The early prototype plates were solid (no windows) and a pretty generic shape, and only used to get the seat bolted into the chassis so we could see where to "window" the final design. We could then mark the best slider locations (again, allowing for the seat to be aligned with the steering wheel) so the final design could be cut next.

The driver's and passenger's side brackets were then CNC cut on our table, with slots for the reinforcing ribs. Then the ribs were cut and those were welded onto the bottom side to make the design much more rigid. We need that rigidity because we also have lap belt and anti-sub anchors built into the plate assembly. As we have said before, this is the shortest, most rigid platform design out there that you can mount side brackets and/or sliders to.

We were busy working on several new seat bracket base designs in the Summer and Fall of 2024, but managed to get the production ready E36 seat bracket bases built for both sides and powder coated before our track test in mid October. You can see the Sparco harnesses and OEM seat belts in the image above right.

STEERING WHEEL, QUICK RELEASE & STEERING LOCK DISABLED

August 19th we started the steering wheel replacement work, which included an NRG quick release that has a functional 2-pin pass-thru so we can have a working horn - for both the E36 and E30 projects. We need a horn on both cars for street use, and it comes in handy in paddock and grid, too.

We actually started with a Sparco model "323" steering wheel for this E36, but at the same time I had ordered this MOMO Montecarlo alcantera wheel for the E30 and it just felt SO much better. I sent the Sparco wheel back and got another MOMO Montecarlo alcantera in 350 mm this time, with the optional red stitching and red born button.

Initially we had the 320mm wheel on the E36, but we later upgraded to a second 350mm wheel, which allows for a better look at the gauges and slows down the steering a bit - which as an autocrosser at heart, really helps slow down my jerky inputs on track.

Before the steering wheel work we had to tackle the removal of the steering wheel lock. This is a job we have done countless times on E36 models, so I sent Christian one of our old forum write-ups on this and he tackled that in a few minutes - you have to know where to drill a hole, then yank out a spring, and you are good. This way if we ever have to turn the key off while on track the steering doesn't lock.

We also tried a couple of different NRG QR hub kits, starting with the "SFI" rated one (above left) but ended up with this "Gen 2.5" model (above right). This came form some miscommunication with a buddy and his race car, but I was able to send that back and get the correct horn compatible model from NRG. A little more expensive but not too much. NOTE - I used to be a "quick release snob" and only used $400 Sparco or Lifeline units. Using an NRG in a buddy's race car cured me of that. The price is good, they make SFI approved versions, and they aren't super thick.

Before we could start we needed a replacement clock spring, which I found on marketplace and picked up the same day (the original was busted). The clock spring assembly (above right) allows for the pair of wiring pass-throus to the stock steering column, and we are those for our horn. You could easily use those for a push to talk radio or anything else.

The adapter hub from NRG is bolted onto the column in the above left pic, with the horn circuit connected through the clock spring and column wiring. That inner piece of the QR assembly is then bolted to the hub adapter. Then the opposite end of the QR assembly is bolted to the 6-bolt, 70mm bolt circle that is on virtually all Sparco and MOMO steering wheels.

The image above is from early September 2024, when we had the smaller 320 mm MOMO wheel installed. the larger diameter 350mm wheel fits the E36 so much better! I had been using 320-330mm wheels for my last two E46 models and they were always covering up gauges. I won't make that mistake again (I hope).

MCS RR2 COILOVER INSTALL

In late August we received our coilover dampers from Motion Control Suspension for this car - this set of remote reservoir 2 way adjustables, or what we call the RR2 model. I pick these remote doubles for most of our shop cars - I know how to adjust them for the best performance, they give us the most stroke, and the best damping curves for our cars.

This was probably the most major upgrade we will make to this project, and is worth a lot of time drop once we have the car dialed in. Ideally we would have made some "baseline laps" with the stock suspension and wheels/tires, but the OEM dampers were blown and the tires were all dry rotted junk. So our first test will be on MCS RR2 suspension - which is pretty deep down the list of things we recommend for most folks, but I knew we would be here eventually.

I personally built the camper plates and shock mounts for this set going onto our car, and it gave me a chance to triple check the bushing setup for the struts and shocks from our database entries.

We have sold countless numbers of E36 dampers and our stainless steel bushing call-outs were spot on, allowing for the most bump travel and perfect thread engagement on the strut (above left) and rear shock (above right). I assembled these with our springs, perches, and all the rest. I decided to keep the rear damper with the "divorced" spring setup in the stock location, but using our ride height adjusters and alignment cones.

We setup our dampers with our GTR spring rates, which is as high as we go on any E36 without aero. This uses 600 #/in front springs and 750 #/in rears, which is what we used on our 1997 M3 from 2006-2014. Amy is very comfortable on this spring rate, as she racer the 1997 on these rates for many years. Christian got the fronts installed quickly and we got enough pictures to make a proper E36 damper install gallery, too.

Out back the rear shocks are installed in the traditional non-inverted layout, which is where the lower eye bolts onto the stock lower mount and the "pin" upper goes through our spherical upper shock mount. This gets the rebound knob in the trunk for easy access to make adjustments.

The compression adjustments for the RR2 models are on the remote reservoirs. We like to make custom brackets to mount these for easy access, and up front the brackets were made from sheet aluminum. The hoses are long enough to allow them to route under the frame rail and into the engine bay. We picked a good spot underhood and mounted the reservoirs vertically, right to the radiator support behind the headlights (and away from radiator heat).

Out back the hoses had quick disconnects, but like all monotubes charged with 180+ psi Nitrogen, you have to bleed off the Nitrogen before you can disconnect the lines - so we try not to mess with that unless we have to. We have been routing the rear reservoirs through the trunk baffle plastics, which just pop out of the trunk sheet metal. A small notch on one end allow the hose to fit without major surgery. Our crew also made some reservoir brackets that bolt to the rear frame rails in the trunk also.

This install spanned a few weeks, while other work was proceeding, and we put the M3 on the scales on August 22nd, where we saw 2910 pound weight - very encouraging! We still have the very heavy exhaust on the car, the air conditioning, and some other things we can legally remove for Max class Time Trial use.

I was very happy with the initial ride heights - which we copied from our 1997 M3's (above left) specs we came up with back in 2005. But that car had properly sized wheels and heavily rolled fenders. As soon as we added the E46 spec 18x9.5" wheels and 265mm tires to Project #Hellrotten, we ran into major rubbing issues. We went through several ride height changes and fender rolls to get through the first two track tests - and none of them were "right" (the rear tires rubbed hard). We are just now properly fixing in late December 2024 - cutting the fenders and adding widebody flares. More on that next time!

REAR TIE DOWN HOOKS

Most of the time we will trailer this car to and from the track, so the car needs to be strapped down properly. I dislike strapping down to the wheels, but the BMW does have the "T-hook" slots that are somewhat easy to access.

But I am lazy, and speeding up my loading and unloading times is always welcome. So when we have access to the underside of the car (ie: no diffuser) we add these tie down hooks to the lower shock mount. We make these for a number of cars, and have optional longer lower shock mounts to make these 1/4" thick pieces fit onto the steel lower mounting point. Makes tie down straps super easy to install and remove - much quicker than the T-hooks.

OIL PUMP DRIVE + BAFFLE UPGRADE (ACHILLES)

One of the most notorious failures of these BMW S50/52 and M50/52 engines is the chain driven oil pump drive falling off. And when that happens the oil pressure goes to ZERO, and trust me - that is ZERO fun. I lost a couple of E46 M54 engines from this issue. Our 1997 M3's S52 lasted for a long time in racing because we welded the nut on, but there are better modern solutions to that ghetto fix we did to that car in 2004.

We also have a TON of oil leaks that have sprayed the underside of this car in black goo for decades - that just makes me crazy. So we ordered the oil pump and oil pan upgrade parts and Christian hung the engine from above and the subframe and rack came off for a deep cleaning.

With the oil pan off I asked Christian to also remove the valve cover, which was also suffering from multiple gasket leaks. All of that needed major cleaning and new gaskets, of course.

We tapped Achilles Motorsports to supply the oil pan baffle kit as well as their oil pump shaft upgrade. This is a common fix with a new oil pump shaft that incorporates a unique shaft end shape that mates to the hole in the sprocket, then a drilled bolt for safety wire. This is a double secured sprocket so it cannot come off without breaking the shaft.

I cleaned up the subframe, steering rack, oil pan and valve cover in our parts cleaner. Lots of heat, soapy water, and scrubbing made a dent in these parts, but the oil pan needed to be spotless since we had to TIG weld in the baffle kit.

I drove over to our "sister shop" HorsePower Research with the oil pan and valve cover, which both went through their sonic cleaner for a 10 minute cycle. I did a little scrubbing in their parts washer, then sent them through the sonic one more time. The magnesium valve cover's ugly gold factory coating was even peeling off that this point. Above right you can see the Achilles Motorsport aluminum oil pan baffle kit, which has two swinging trap doors to keep the oil pump pickup submerged under cornering and braking.

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**Fair!** · 12-26-2024, 06:35 PM

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Myles mocked up the baffle into the now spotless oil pan and added TIG weld bead to the spots that Achilles recommends. This baffle upgrade is good insurance to do before taking any BMW S50 on track.

I spent some time making the steering rack and subframe spotless, and the subframe paint was well preserved under all of that oily grime. Christian got the oil pan and pump shaft upgrade wrapped up in late August 2024.

With no more oil leaks we can finally put some proper oil into this S50 - so a full fill of Motul 8100 5W40 synthetic oil was added, and it was indeed leak free.

Other than the old exhaust system, the underside of the front of this very neglected M3 was looking pretty clean. After this work we only had a small power steering leak that remaining, and parts were ordered to fix that next.

ENGINE BAY DETAIL

One of the things that triggers me (beyond fluid leaks) is a messy engine bay. This M3 was pretty nasty looking under the hood when we removed it from the barn, so that whole area needed a major cleanup. This M3 has to show what Vorshlag is about, and all of our cars have clean engine bays at all times. Sure, the nappy paint is not great, but all in good time.

We have come a long way from that pair of nasty images above, with the underside now cleaned up as shown in the previous above. But the engine bay from up top needed help - that started with a power wash in July, but in August I started an engine bay detail job with liberal use of WD40 on all surfaces. I spray everything with the BIG BLAST can, let the fluid it sit for a bit, blow all of that liquid around with compressed air, then wipe down all surfaces and rubber.

That clean up made a big improvement to all of the painted surfaces and plastics, and especially the rubber bits. This is before the cowl panel plastics had arrived from Sweden, but we were getting closer.

Next the sonic cleaned valve cover was run through our bead blaster a couple of times to get the top side down to bare metal. This was then sprayed with two coats of primer and then 3 coats of gloss red Ceramic engine paint over the course of a few days.

Christian put the black plastic panel over the valve cover, which covers up the 6 ignition coils. But I liked the red valve cover too much uncovered, so that "BMW M Power" plastic bit came off and will not go back on. I am finally not embarrassed to open the hood on this old thang!

MOMO 18X9.5" WHEEL, 265MM TIRE AND FENDER ROLL

Don't think I am losing my touch here - this is just a temporary wheel and tire package! Why? Because the stock 17x7.5" wheels and 235mm tires were beyond using. These tires dated back to the stone age, and I was cautious even driving them around the block (one wouldn't hold air long).

Instead of buying a set of tires to use for the baseline test, we looked in the shop and found a brand new set of MOMO 18x9.5" ET35 wheels with a BMW bolt pattern. Now these are not ideal for the E36 chassis, as they have an offset better suited to use on the rear of an E46 non-M chassis (we bought these for an E46 ZHP we are restoring). But these were on hand, and I had also scored a set of the previous generation Bridgestone RE-71R tires on closeout in 265/35R18 size.

To be clear: I AM NOT ENDORSING THIS MODEL OR SIZE TIRE FOR ANY E36. These DO NOT FIT this chassis well, as we will show from here through the first two track tests. It took a LOT of compromises to fit this tire, including butchering the fenders and raising the ride heights to a 4x4 level. These wheels are also heavy AF, as you can see in the scale pics. Anchors, but again - I had them on hand and it was all "new". The DOT dates on the Bridgestones were 2019, but the tires were stored indoors and still had mold release (which protects them from oxidation) so they actually worked great on track.

These wheels used to be called something else but they are now the MOMO "Catania" - we bought them in 2022 for a decent price. The wheels and tires were installed in September with a 12mm spacer up front, but we clearly needed more camber and a major fender roll to clear the fender lips. Again, these do not have the right offset for an E36 rear.

We also installed Vorshlag 90mm front wheel studs and our 12mm spacer as noted. The rear was used without a spacer and our 75mm wheel studs. We do recommend a light coat of anti-sieze on the outer threads where they interface with the lug nuts, and torque specs are 85-90 ft-lbs on these M12-1.5 threaded fasteners.

I had Christian take our Eastwood fender roller and work the fenders at all four corners, but it took some serious persuasion. To fit this wide of a tire you have to not care about the paint or outer shape of the fenders - we rolled them, cracked paint, distorted the fender shape, and they still barely fit.

A better option would have been a 17x9" wheel and 255/40R17 tire (which still needs a roll) - a popular size we have used before, but this was not our end goal and I did not want to buy an "interim" wheel and tire set.

There were consequences of running this tire width and wheel offset, which I will cover below. The wheels looked all right I guess, and while we had run wider 18x10" wheels and 265/35R18 tires on our 1997 M3, we had a better offset and more inner fender work to make those fit (and they still rubbed, if I'm going to be completely honest).

RAISE RIDE HEIGHTS!

On September 10th, I took the M3 on its first test drive with the MCS setup and the 18x9.5" wheels and 265mm Bridgestones, with ride heights set like our silver 97 M3 at 12" rear and 12.5" front. Yikes! The tire rub was off the charts just on a slow drive around the block.

We immediately raised the ride heights a half inch at both ends, as shown above right. That still wasn't enough and we would fight tire rub at the next two track tests until we finally cut the outer fender lips off and went to flares.

ALIGNMENT #1 - SEPT 9, 2024

We went pretty aggressive on the first alignment, but it worked well on track and gave us some much needed tire clearance at all four corners.

We could get more front camber if needed but this will work for the relatively small 265mm RE71R 200TW tire we have now. It was actually very well balanced on track with this alignment - zero front toe, lots of camber, and .33deg rear doe in.

GOOD TOW HOOKS ARE HARD TO FIND

For the last 20 years there has been a "Race to the bottom" on costs for cheap screw-in tow hooks for BMW models. The unit below left was once $40 is now $10 shipped, and the quality has gotten progressively worse. These easily bend even with gentle straight winching of a rolling car into a trailer. The hardware is also super cheap and rattles loose and falls out.

So in July when we revived this barn find I immediately began looking for a better tow hook to use front and rear with the factory threaded bungs. And we stumbled upon this Mishimoto tow hook kit that looked promising, but it was on close out. Normally $183 each (and price has some correlation to quality), some colors were as cheap as $63 each. So I ordered two of those in black and polished aluminum and waited...

It took several emails and follow ups to that original order but in late September they found some of the last inventory of these and sent the pair. I also bought one of the $10 Amazon versions to compare. The Mishimoto tow hooks are significantly better built and use 7075 aluminum for the hooks, with steel used in the various shaft pieces. It is a real shame these are no longer available - we have since used these many times and they work great.

We even had to use the cheap cast aluminum Amazon hook for one winch trip into the trailer (above left), and while it worked, it did get a bent after use. The Mishi tow hooks have been used multiple times with zero issues.

We do like to replace the removable covers for the front and rear hooks so we mark and cut them to fight with the tow hooks installed. Looks a little more factory and less janky. If we do not find a new supplier that makes REAL tow hooks instead of the "faux hooks" that are flooding the market, maybe Vorshlag will jump in with a better option. We've not been super impressed with some of the tow hooks we have used on many cars...

INJECTOR ISSUES AND VACUUM LEAKS FIXED

The M3 sat for at least 7 years and had rotted a bunch of vacuum lines, rubber bits, and seals in the intake tract - which led to a real chase to fix all of the vacuum lines. We used our smoke machine on this car several times, replaced a dozen feet of vacuum hoses, and kept finding more leaks every time I test drove the car.

All vacuum hose found leaking was replaced in entirety with better silicone versions in 4mm, 5mm, and 6mm sizes that I sourced off of Amazon. It is a good idea to keep a 10' section of these sizes on hand for German cars of this era.

One smoke test found this intake elbow with a massive crack in it - we have an aftermarket silicone version on hand for a future upgrade with a larger MAF sensor, but we don't want to "tune" the engine for that yet. So an OEM replacement for $15 off Amazon worked to fix that leak, and in this video from October 7th we had the S50 running as good as it ever had.

We had sent the injectors off for this S50 (not S52 as shown) and had them cleaned and flow tested. Prior to the cleaning 2 of them had no flow at all, so this was money well spent on these 30 year old injectors before we ever tried to fire the engine. The injector cleaner we used was not enough to get those two stuck guys going - or so we thought. Next time if I see a "fail" those after a test, those injectors will get replaced outright.

This next part of the repairs was tackled after Track Test #1

At the first track test (see below) I immediately noticed a rough running engine once again. It got worse over two sessions, so on October 20th when we had the car unloaded again I asked Christian to "smoke" the intake tract once again, and yet another new leak was found. This idle control valve connector was the culprit this time...

That was replaced, no vacuum leak, but the car still ran rough. We plan to build a full race exhaust but again, we don't want to "tune" the car yet so the factory catalysts were cut open to inspect and make sure they weren't plugged up. They were not so the outer skin was carefully reinstalled and welded in place.

The sticky hydraulic follower was also making noise again so the rest of the bottle of the Lucas "Oil Stabilizer" was added. We also took a compression check again, so make sure everything was still good. The 179-180 psi numbers looked dang near perfect, so it wasn't a mechanical issue.

Finally it was time to double check some systems - I was sure that we had a missing cylinder! And sure enough, one of the "cleaned and tested" injectors was not firing. The wiring was checked, and it was just a "bad injector". I bought one replacement (since we might replace them all with aftermarket injectors at some point) and that arrived from FCP Euro on October 31st.

Click the image above to see the video and hear the little S50 run smoothly with all 6 injectors working. The various vacuum leaks and all 6 injectors firing reliably transformed the little S50 for our second track test. The car has been running smoothly every since - finally!

KIRK RACING ROLL BAR + REWORK

Safety is important to me and Amy both, and we didn't want to skip on the rollover protection or harness mounting. There aren't "good" harness bars made for the E36 chassis, and I didn't feel like burning the hours to make something that half of you reading here would only scoff at.

After looking at $1800-2000+ 4-point roll bars, I went back to what we know and have used many times with this 4-point kit from Kirk Racing. We have used these on E30 and E46 models before, but never an E36. How different could it be? Well at $650 for the raw kit + $200 shipping, we definitely "got what we paid for", and no more.

Christian started stripping the back seat area Sept 23rd and got the chassis ready for the roll bar. the Sparco front seats were removed at this time. The upper back seats (33 pounds) and lower seat cushion were already removed. In SCCA Time Trial Max class with "Level 2 safety" (adding the 4-point roll bar) we can remove those pieces as well as the rear interior panels, rear carpets and the rear undercoating. All in we removed 80 pounds of junk from the back seat.

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**Fair!** · 12-26-2024, 06:53 PM

continued from above

When the kit arrived October 7th I was not too pleased with the crude mounting plates that Kirk had welded onto the 4 points that meet the chassis. None of the plates matched the shape of the floor or fender wells at all, leaving large gaps on the main floor mounts. So we did what we knew we had to do - reworked the mounting feet.

Christian and Myles cut off the two mounting plates for the main hoop, designed larger and better fitting feet, and CNC cut those. The new, larger floor plates have a bend in them that matches the curvature of the floor now. This also sits on the stronger, outer portion of the floor sheet metal right at the edge where it meets a vertical portion - and has an overlapping ledge underneath. This wasn't that hard to do right - just disappointed that we had to do this.

The new "feet" were tack welded to the 4-point hoop while sitting in the car, then the "bolt on" rear downbars had their feet curved to match the wheel well. Then the 2 new feet and all tube junctions were fully MIG welded on the bench before going to our powder coater in early October 8th, one day after the 4-point kit arrived.

We waited 8 days for the gloss red powder coating to be completed, but it was worth it. We also made new "doubler" plates for the main hoop and bent the rear feet - which were powder coated also.

We normally budget 8 hours to test fit, tack weld, fully weld, and install a 4-point roll bar. We burned an extra 3 hours cutting the main hoop feet off and making new ones, but I'm much happier with how these mount than the way this kit came.

In the end the roll bar added 63 pounds to the M3, gives us a very good place to mount the 6-point harness shoulder straps from, and adds some rollover protection. It was still cost effective, but looking back in hindsight we maybe should have just built our own 4-point roll bar. A new design would have a few other improvements, too. Still, at $850 + powder coating costs, this was a relatively "cheap" upgrade. I do see why some of these roll bar kits cost $2000 now.

TRUNK BULKHEAD PANEL

Was a bulkhead panel separating the passenger cabin from the trunk completely necessary? We don't have anything mounted in the trunk that needs to be kept away from people - yet - but we do have plans for a remote fuel pump surge tank that I don't want spraying fuel on people, in a "worst case" situation. This panel cuts down on noise inside the cabin for street and even track driving - since the back seat cushions are now gone (the seats muffle road noise quite a bit).

Making a really nice bulkhead panel is also a bit of a "flex", and I'm not above that for one of our shop cars. This was one of the first "fab" jobs I had given to Christian, and he took it to the next level. From cardboard to aluminum sheet in an hour, which I was happy enough with. I just asked him to add a brushed finish, but he went beyond that.

Not only did he add the brushed finish with our burnishing tool, he added some bead rolled ribs to the perimeter and an "X" in the middle. Heck yes!

To help sound proof this I asked him to add the 1" wide x 1/8" thick weatherstrip foam tape we keep in stock to the perimeter. This was then bolted in using some stainless button heads threaded into some rivnuts added to the interior. The whole thing came in at 4.9 pounds and it looks amazing. But it also acted as a bass drum at the first track test... I will explain that in the Track Test #1 write-up.

3D PRINTED ALTERNATOR DUCT

Most of you E36 fanatics know that many BMW alternators are "air cooled" with special ducting that runs from the front radiator shrouding all the way to a housing on the back of the alternator. All of that was rotten on this car, but I had slowly been piecing together all of the necessary parts.

Some of the OEM parts are No Longer Available (NLA) new, so the aftermarket has stepped up to make this plastic part that we couldn't find. But unlike a traditional cast plastic part, this is 3D printed by Treedy Labs.

This is actually the first useful 3D printed part for a car I've ever purchased, and these Treedy Labs guys have since gotten more of my money for parts for both the E30 and E46 we are restoring. The fit was great and the quality was, well, about what you'd expect for a 3D printed part. Not great, not terrible, matched the price we paid. This isn't a "mission critical" part so I'm OK with it.

MOUNTING GARMIN CATALYST (VER 1)

This was our first attempt at adding the predictive lap timer and GPS data logger to the E36 - which has a camera that overlays this data to. The Garmin Catalyst is well known and Amy really enjoyed using this in her 2023 BRZ in 2023 and her 2024 Darkhorse in 2024, so we added the RAM branded mount to the E36 and wired up the camera.

Sadly, this location was not ideal for GPS coverage (the Garmin needs a direct view to the sky), and we got no usable video / data from this at the first track test. I will show where we remounted that for track test 2 later in this post.

UPGRADED SWAYBARS

During the MCS install we of course changed the OEM swaybars for aftermarket adjustable units. Up front we used We used the Whiteline BBF38Z (27mm with 3 adjustments per side) ran Whiteline endlinks up front, which are adjustable in length and have weather sealed OEM style ball joint ends.

Out back we used a Whiteline BBR38Z, which has a 22mm diameter with 2 adjustments per side. These came with some less than awe inspiring endlinks, but the better Hotchkis units we wanted were on a long backorder.

As we always preach about, of course we shimmed the poly mounting bushings (which come with the WL parts) and added grease zerks to allow for "pinkie finger effort" rotation of the bar once mounted. This removes all swaybar bind in the mounting bushings, which is super common and makes handling unpredictable. Annual greasing will keep these noiseless and bind free for decades.

TRACK TEST 1 - OCT 17, 2024 - PRETTY HORRIBLE

At long last I felt like we had a good enough setup to take to the track - for the first laps this car has ever made. This was supposed to be our "baseline" lap upon which we would hopefully improve from. I didn't want to hold anything back, because this is already a car with upgraded MCS suspension. I never sandbag any of our track tests.

I went out by myself to a member day at MSR Cresson on their 1.7 CCW course, and I went with a plan - absolutely nothing went to plan. Got there at 9 am, 44F after unloading, and there were not many people driving that day. Drove over to the Sunoco and fueled up with +6 gallons, set tires at 28 psi cold, but these were brand new RE71R tires covered in mold release that needed to be scrubbed in. Set the MCS RR2 dampers to a "good guess" setting of +6 Compression front and back, +8 Rebound front +6 Rebound rear.

I was a little delayed because I had to go back and clean the windshield and some other windows. I setup the Garmin for the first 2 sessions but the dang thing never worked right and I got ZERO video or data from the Catalyst. By the third time out on track I punted and put in a backup video camera with a somewhat janky camera mount (my normal RAM 1" ball to 1/4"-20 adapter was in the Pontini BRZ and the backup was in Trigger!) and the old AiM SOLO for some GPS and lap time data.

In the first session the engine felt a little down on power. First time I hit 90 mph on the front straight the car was shaking violently with massive vibrations. It was so loud I thought the car was shaking apart!!

Came right in, got out of my driving suit, and pulled both rear wheels. A buddy Bryson from Xena Racing and I looked at everything in the rear suspension and axles. I bled the tires down but nothing looked wrong - nothing. Everything spun easily, rear wheel bearings were tight, nothing was touching or making a peep. Reinstalled the wheels and tires, put my gear back on, and went right back out in the same session. Hit 90mph and heard the same thing - on a hunch, I stuck an arm out roof opening and the noise went away. Made another lap and checkers. Fudge.

This was just buffeting through the open roof, and my arm out the hole disrupted airflow enough that the trunk bulkhead panel quit vibrating like a drum. I looked for some piece of trash wood, which I found in paddock. I taped this piece of wood to the roof to simulate the factory pop-up spoiler ahead of the sunroof opening. Probably used too much tape, but the paint is fried so who cares? Waited 30 minutes for another session to open up, meanwhile I fiddled with the Garmin but it just never worked - these things can be super flaky.

Went out again and realized the seat slider stuck too far forward and uncomfortable (we had a bolt in the wrong place). Brakes and tires worked great, just made as quick out lap to get heat in the tires, get a feel for the car. Came into the hot pits and bled the tires down to 31 psi hot. My final stint out was only 3 laps, but it felt even more down on power. Definitely down at least 1 cylinder, and it was getting worse. Of course that's the only timed laps I got that day (AiM SOLO).

Really sluggish in 3rd gear, and I didn't want to hurt the engine. This 1:32 lap is hardly a "baseline lap" and more of a shake down. This was not a great track test, and I will need to re-do this whole thing after we fix the engine misfire issue. We won't have any data since this is an OBD1 car, so it was a lot of driving (4 hours towing) to get 6 lousy laps over 3 sessions, but it needed to be done.

WEIGHT CHECK OCT 17, 2024

Got back to the shop the day of Track Test 1 and I wanted to get a weight before we brought the car into the shop. Yikes, the car got fat!

Gained 103 pounds since our August weight check, but that delta is accounted for like this:

Difference in stock 17x7.5" wheels and 18x9.5" wheels = 28.4 pounds
Addition of rear roll bar = 63 pounds
Rear trunk bulkhead = 4.9 pounds
Small difference in fuel load + added 6-point harnesses = approx 10 pounds

We took the August 2910 lb weight with the smaller stock wheels and without the back seat in the car, before we added the roll bar. We will start chasing pounds now.

I took this second picture to note the ride height, which still looked high but had ample tire rub in the slow-ish laps I took. We raised the rear ride height even more after this track test.

AC TESTING AND REMOVAL (CHASING POUNDS)

Now that the car exceeded 3000 pounds on the scales, I was a bit spooked and started looking for areas to trim some weight. This was one of the first victims - the factory air conditioning system.

Now I will say this - removing the air con from a car we are calling "dual purpose" seems dumb, and it is - but after testing the system with our lines and vacuum pump, we saw some pretty big leaks. Repairs for this car could exceed $1000 in parts alone, so I made the call and Christian pulled the "easy" parts off - the lines, the compressor, accumulator, and the condenser (not shown or weighed).

Removing that set of lines from the compressor to the firewall also freed up some room in the engine bay, which will come in handy when we add the stainless header we have ordered. Christian made a block off plate for the firewall port to to seal off the interior air con bits (evap core), so if we ever decide to add the air con system back that the interior bits aren't all full of junk and rot.

ARMREST DELETE - NEW CENTER CONSOLE

This wasn't really done as a weight reduction, but as a fix for the "I keep hitting my elbow on this dang arm rest" problem from Track Test #1. All of my E46 BMW cars in the past got the "armrest delete" consoles, but from what we can gather, all E36 coupe models came with this useless flip up arm rest.

I looked around and could only find E36 sedan models without the armrest. they are a different length but I took a chance and bought this tan one from eBay for $33 shipped. We had some black vinyl die spray to refinish that to match our black E36 interior.

After that was cleaned in the parts washer, scuffed with Scotch Brite, washed with soap and water, then wiped down with paint prep (above left) it was hit with a few coats of black dye and allowed to dry overnight. It really looked great and matched well! The front edge of this sedan console lines up with the "shifter" section of the console, but the rear mounting was different for the coupe model. Christian made a simple aluminum bracket that adapted the sedan console to the factory coupe rear mount, easy peasie.

The new "armrest delete" sedan console was then bolted in and it looks freagin factory. I have since driven the car on track and the missing arm rest is noticeable - no longer banging my elbow on every shift. The 4.5 pound drop was just a bonus.

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**Fair!** · 12-26-2024, 07:15 PM

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INSTALL VORSHLAG ENGINE AND TRANSMISSION MOUNTS

One of the more frustrating issues in our first track test - other then the complete lack of power - was how poorly the shifting felt in the car. Long ago we realized how terrible the OEM driveline mounts were in these cars (they are fluid filled hydraulic mounts) and we designed a series of engine and transmission mounts for the E36 chassis that we have sold since 2007 and redesigned in 2013.

These mounts dramatically change how the shifter feels because, like most BMWs, the shifter is mounted to the BODY while the DRIVETRAIN moves independently on the squishy factory mounts. It doesn't take much engine torque for the transmission to move relative to the body mounted shifter, which makes the 4-to-1 money downshift possible, when you just meant to do a 4th to 3rd downshift. This happened to me at track test #1, but I knew to watch for this, could tell it wasn't right, and put the clutch in before the engine saw "all the revs".

We ran out of stock of the CNC machined parts for a bit in 2024, as the sales of these seemed to taper off. After getting to drive an E36 on track with the stock mounts, I was quickly reminded how important these are! So we tooled up and made another big batch for inventory over the summer - and Project Hellrotten got one of the first ones built.

I chose the Nylon engine mounts and the red 95A durometer poly transmission mounts, which are the most firm setup we sell. Wow - what a difference! Night and day driving improvement at Track Test #2. It kept me from buying a $1000 shifter after driving the car with these mounts, at least for a little while.

LAST LEAK (POWER STEERING) FIXED!

After all of the gunk and grime had been cleaned from underneath the engine and crossmember, we had one small dripping leak left - which was evident after towing the car back from track test # 1. I ordered a small hose for the low pressure suction connection from the loop cooler and Christian got that swapped out on November 8th, before track test #2.

We haven't had a single drop leak from any system since this repair - finally!

HOTCHKIS REAR ENDLINKS (IS THIS COMPANY OVER?)

I wasn't thrilled with the end links that came with the Whiteline rear swaybar so we ordered these Hotchkis adjustable units in July of 2024. They arrived in late November of 2024, which is pretty fast for this company of late. Great products, but they are always out of stock.

We had to take down all of the swaybar and end link options from this company years ago, because ever since about 2020 the lead times went to 6-12 months on anything. That does not look good and they have made statements like "(we) are currently reorganizing and are temporarily under construction" or "Hotchkis is working to fulfill orders as soon as possible, but (they are) experiencing some communication issues". This could be code for "we are going out of business", but what do I know?

MOUNTING GARMIN CATALYST (VER 2)

On November 22nd, it was time to make a better mount for the Garmin Catalyst lap timer to get ready for Track Test #2. It needed to be away from the shifter (in case I bought the long RTD / CAE style unit) where the first version of this mount put it. I also wanted a dedicated USB port for the Garmin and the backup AiM SOLO or backup video camera, as the cig adapter in the center console was super flaky.

I looked more closely at the interior with Christian this time. We talked about making a metal bracket mount above the glove box, like we did on the 2024 Mustang Darkhorse. That led to this finding the passenger side airbag, and shortly afterwards 6.8 pounds of explosives were removed from the dash. Into that gap slid the new aluminum bracket, which the RAM base and a dual USB port / battery voltage meter is attached.

This still allows the Garmin to be placed in view of the driver, ans also uncluttered the center stack panel - so much so that we could reinstall the radio. This new location leaves room for the mega-tall race shifter when we need to install that. The better USB power for the Garmin should help make it more reliable? (it did not)

TRACK TEST 2 - NOV 29, 2024 - LESS HORRIBLE

We planned for this track test on the Friday after Thanksgiving, which was a member day at MSR Cresson that is often under attended. But from the point I planned it until the day we got there, they changed the direction of running to the 1.7 CW course - which is backwards from our normal 1.7 CCW test course. I figured this out as I pulled into the grid - crap! Not the same course / comparison when you run a track in another direction.

The sunroof panel had not arrived yet, so the guys made me another "spoiler" with a chunk of material, which worked again. We planned a later morning arrival time, and were on track by 11:30 am. Amy joined me that day, and she hates being cold - this later arrival let us beat the cold early morning weather (31F), giving us temps in the high 40s/low 50 F range, which was nearly perfect. I went out first with with 6 gallons of fuel in the tank, which thought would be enough. Nope! This led to major fuel starve on right hand turns (which the 1.7 CW course is full of).

ABS trouble light was lit on the dash as I drove it out of the trailer, and as expected the ABS did NOT work at all. This made it super easy to lock the front tires, which is a problem we will tackle before the next track test. After just a lap of fuel starve I dove into the paddock, grabbed my wallet, drove to the pumps, got a full tank of 94 octane, and went right back out - this time with Amy riding shotgun. The Garmin stopped working in the middle of this stint. When these units "lose the camera" the timer stops working, too. Super frustrating. I bled the tires down to 33F/32R hot pressures and reset the MCS RR2 dampers to Compression +3 front/rear and +9/+6 Rebound. That smoothed things out a lot.

We stuck the dual 1080P video camera RoadKeeper and the AiM SOLO into the car for the rest of the day. I was over braking everything and then trying hard to avoid lockup and drove to a best lap of 1:27.9 with Amy riding shotgun. I thought I was "showing her the course" but apparently she is better on the 1.7 CW than me. This car is for her so she drove it for the rest of the day, after my super short stint. I rode for a few laps in the right seat on the next stint, then got out and let her drive solo.

The in-car video from this test shows Amy's best lap, and she straight smoked my times. You can also see how compromised the braking is when the ABS stops working in the first part of the video. She had 1:26.350 best running by herself, and she put in a string of 1:26 laps. This CW direction is about a second slower than the 1.7 CCW, so that translates roughly to a 1:25 lap - which is getting... quick-ish?

Now that we have "full power" and the car was 6 seconds quicker than Track Test #1, which meant we were pushing everything harder. That translated to higher cornering loads - and those 1.45g peak lateral g numbers meant that rear tire rub was now horrific. I simply couldn't "drive around" the tire rub noise. Amy didn't care or couldn't hear it, so she just sent it. The 2019 era RE71R tires worked great, as did the cheap RockAuto brake pads - keeps us from buying pricey track pads until we do the planned BBK upgrade.

Amy has a lot of laps in a similar E36 M3, and was super happy with her times being that much faster than me. I just couldn't "unhear" the heavy tire rub, and it got to me - but she put me in my place that day!

Notes: Seat needs to go up and one more notch forward for Amy. Speaker grill popped out on me, bouncing around back seat areas. Center console change was nice. Coolant temp mid mark all day, would be really nice to have an oil pressure gauge, though. Shifter now feels notchy, clutch releases right off the floor. Exhaust note is super quiet, hard to hear the engine revs.

We took close to 30 laps that day (some with the Garmin, then these 22 laps with the AiM) and the car was pretty reliable. Frustrated about the ABS and tire rub, but we can fix all of that. Lots more work to do, and we am hoping to have the car prepped with cut fenders/flares added and working ABS for another test on the proper 1.7 CCW course maybe before the end of 2024, or very soon after.

WHAT'S NEXT?

There is much more to cover next time but this write-up is running super long, so I am gonna cut it short here. I finally picked a widebody flare kit and ordered that from Eastern Europe, and the first thing we did was install the sunroof panel. The fender clearancing and flare install work is ongoing as I write this, too. We have plans for an 18x11 or 18x12" wheel and 295 or 315mm tire for Max 5 class use next season - hence the giant flares.

We are also chasing down the ABS issue, getting ready for another track test in the coming week or so. We still have lots of parts ready to install, including header, muffler, cold air parts, and more. Started looking at an aftermarket EFI system, since tuning these ECMs is so clunky (burn a chip!) and we have to get data into a logger of some kind, as well as a proper digital dash so we can see it while driving. More on all of this next time.

Thanks for reading!

**Taper** · 05-19-2025, 06:22 AM

As always excelent post!

**Fair!** · 10-17-2025, 04:53 PM

Project Update - October 17, 2025: Looks like I waited about 10 months to update this project, apologies for that. We've actually had a heck of a year in SCCA Time Trial Max5 class in this car, but this entry - the longest I've ever written with SIX sections - covers three months of intense work on our little Project #Hellrotten E36 M3 during a VERY busy time at the shop.

During January and February I was busy supporting a customer who was trying to run as many SCCA and NASA races to get his Pro license for IMSA, so he could run the Darkhorse-R series in 2025. We worked on his blue Mustang (below left) simultaneously with the red M3 plus my "less than ideal" season working on my Time Attack Mustang (below right). It was VERY hectic.

So much has happened to the M3 in this 3 month period in early 2025 - the widebody overfenders, 18x11" wheels and 315mm tires, full aero front and rear, custom exhaust and header, Link ECU upgrade, massive weight reduction with a "lightweight" interior upgrade, a single track test, and more. Let's jump into work that picked up where we left off last time - early December of 2024.

SUNROOF DELETE PANEL INSTALLED

The factory sunroof cassette is heavy and we pulled this out back at the beginning of this project, July of 2024. We should have immediately installed a sunroof delete panel, as we noticed MASSIVE buffeting on track with the open hole and missing air deflector. And my piece of wood taped to the roof was just silly - and some of my crew turned it into a red hat.

Fully 5 months later, right before the widebody kit went on, this sunroof panel was installed (it was ordered from the same supplier as the flares). And it fit really well, and sealed up the opening perfectly.

This was installed with no RTV sealant, just the bolts into the cassette flange and some weatherstrip stuck on. It worked fine, but we had no rain events or other worries.

Our crew put some 1/8" x 1" wide weatherstrip around the edge that mates to the bodywork, and we ran it like this all season. It is waterproof, as we have since tested.

In March of 2025 the sunroof delete panel was painted, weighed (3.9 pounds), and reinstalled with fresh weatherstrip foam in place around the perimeter. It looks OEM from the outside, yet it weighs 31.9 pounds lighter - weight dropped way up top, and it gives me some additional head room when I drive it.

FITMENT LAPS PHASE 3 WIDEBODY OVER-FENDER INSTALL

I picked these Fitment Labs overfenders after much deliberation, research, questions sent to manufacturers, and after looking at a bunch of drift cars. That's honestly who buys most of this widebody stuff, and Fitment Labs supplies to many BMW folks in that field - and to a handful of road course junkies who understand the power of wide tires.

This kit allowed the most room of all of the options we looked at, the price was great, and they answered my questions quickly. We ordered the E36 coupe Phase 3 kit plus a few options like the sunroof panel and rear lower bumper extension panels. Shipped to us from Europe this kit totaled 1118.00 Euro, which was $1242 USD, before the dollar sank compared to the Euro.

Ordered Nov 12 and it arrived 2 weeks later, so I unboxed it all (found one tiny crack in all of these pieces) and mocked it up on the left side of our E36. We still had the tiny 18x9.5" MOMO wheels installed, which rubbed even with fender rolling. After the flares were installed they looked positively ridiculous!

I took these measurements because nobody ever seems to bother - the additional tire clearance was even more up front than I had hoped, and plenty out back as well. This measurement was to the outer factory fender lips. These fenders sat for over 6 weeks while we worked on other things.

The front is an overfender - you will need to cut the factory fenders to clear the tire at full bump travel and full steering lock. This is where we started but we cut even more after our first test drive. The front bumper cover needs to be trimmed, as so does the under-headlight trim. And to clear our 315mm tires on 18x11" wheels we cut A LOT.

The rear on a unibody car takes the longest to clearance - figure 10-15+ hours if you do this right. We started with a generous cut, with all suspension clearance upwards (the rear tires don't steer). Christian cut through the outer skin with a 3" cut off wheel.

Then the inner structure is then cut away, but we leave a little bit to bridge the gap to the outer fender. This little flap is then cut into strips and hammer formed upwards, from vertical to horizontal, to help bridge the gap.

Next we tested the rear suspension at full bump travel by removing the rear springs, then compressing the suspension until either the tires run into the inner fender structure that is left (the horizontal portion) or the shocks run out of travel.

The images above show the overlapping "flaps" as they are spot welded to the outer fender skin. These can then be cut off and skip welded for structural integrity. Before you cut or weld anything out back, remove the rear interior panels and HAVE A FIREMAN on standby with a water bottle. As flares pop up (things inside the fender CAN AND WILL catch fire), they can tap the welder on the back to move, put out the flare up, and then get back to welding.

When you are under the welding helmet you cannot see fire until it is too late. This is a 2 person job, every single time! In the top right pic a thin strip of 18ga steel sheet is being welded in to cover up the gaps in the pie cut flaps, to make this all water tight. Lots of skip tack welding with the MIG and you can restore the structure that you have cut away.

At this point we had the front trimmed up to clear at full bump (but not full lock steering) and the rears were trimmed and fully welded. On to another emergency.

ABS UNIT REPAIR

At Track Test #2 we had a weird ABS light come on and some tire lockup, and it was good time for a diversion from all of the fab work above, so Christian tackled the diagnosis of the ABS issue.

The top left image from our connected Autel scanner shows "output of left front outlet valve faulty", and then "fault in power supply of all solenoid valves". So Christian pulled the 3 channel ABS unit out of the engine bay, then unbolted the lower panel that holds the solenoids. WOW! That was pretty corroded inside.

We had another random 3 channel ABS unit in the shop, opened it up, and it looked a lot better - but the ribbon wiring that controls the solenoids was all trashed, literally crumbling. I put word out on Facebook and a BMW guru two towns over had a bunch of parts he gave me to try, and I gave him a few bucks for them. We then swapped in new ABS relay, with no luck.

I found the correct 3 channel ABS computer (inside mounted) for $40 on eBay, but that didn't help either - but now we have spare (I have had one of these fail on another E36). The spare ABS units the guy gave me were 4 channel - that's more work than we wanted to convert our 3 channel car at the moment. So Christian started testing the extra 3 channel ABS unit we had in the shop with the crumbling ribbon wiring, and he did some online research.

He saw that folks had successfully rewired the solenoid controls with just solder and regular stranded wire, to replace the flaky ribbon wiring (you can see the little orange flakes on the table, above left). After testing that all 6 solenoids, which still worked by putting power to them, he just rewired the spare 3 channel unit we had - the non-rusty one. And damn if it didn't fix it!

Video above shows a little driving test in Mexico with the 265mm tires, and now the left front is no longer locking up. We'd test the ABS more fully on track soon with fresher 315mm A052s, where it put down some pretty good numbers.

continued below

**Fair!** · 10-17-2025, 05:14 PM

continued from above

WIDEBODY INSTALL PART 2

After the ABS repairs wrapped up it was time to get back on the flare job and finish up. After the major fab work to clearance the tires was done, it was time to mount the overfenders. There is some adjustment here and I liked the placement we found, then sort of sketched out the spacing for the bolts - and that's where Christian drilled 1/8" holes through the fenders and into the body - we could then hold these panels in place with Clecos fasteners. We all really liked how this was fitting.

We can't drive around with Clecos poking out like Hellraiser's face, and I wanted to attach these semi-permanently - not with rivets, but stainless button head M5 bolts. To do that we needed M5 threaded rivnuts installed on the chassis side. Christian then opened up the 1/8" holes on the body for M5 sized rivnuts, and the pneumatic rivnut installer was put to work.

With the front ready to bolt on, it was time to finally fit the rear. We tweaked the rear overfenders for maximum clearance and pushed the optional rear panels out further than most, and it was again Cleco time.

These looked really good, but the little "lower corner" pieces on the leading edges looked dumb - so we left them off. We will address this later.

This was when the finish welded patch panels on the rear got coated in seam sealer, and it dried overnight. Christian made these little "stand off" brackets based on a simple sketch I showed him, which push the overfenders out further than originally designed - for better venting of high pressure air under the fenders and to hopefully clear more tire.

The next day the seam sealed areas were masked off and the raw steel was hit with zinc-enriched self etching primer. Then the overfenders were all bolted in place.

I took the car on a test drive and it all cleared, but man it looked goofy now with the widebody and narrow tires. Luckily some other parts arrived...

NEW CLUTCH SL4VE CYLINDER

Old car problems always crop up on a 30 year old car, and the clutch actuation seemed funky at our last track test - so I ordered a new clutch sl4ve cylinder, which is the easiest part of the clutch system to replace. Fingers crossed!

The little blue tool above left is a brake line cap, which you slip over the end of a dripping hydraulic line. Squeeze the blue bits and it clamps over the end of the brake hard line. Worked like a champ.

Christian got this swapped out, which fixed the low pedal issue, and shifting went back to normal. I kept thinking the 30 year old clutch was going to force me to upgrade, but a year later and its still going strong.

WHEEL AND TIRE UPGRADE

It is the first of the year in 2025 here and after the Fitment Labs widebody kit was on, but now the 18x9.5" wheels and 265/35R18 tires looked utterly ridiculous. I mean the 265mm tires finally stopped rubbing with all of the clearance hidden behind the fenders, but this looked clownish. Vorshlag is known for putting the big meats on all of our builds, and this one is no different!

We had ordered 18x11" wheels from Forgestar in late 2019 for an E46 endurance car we were building, and they showed up with the wrong bolt pattern. So we ordered them again and made sure they read the 5x120 bolt pattern we spec'd out, and these arrived in April of 2020. A little on the heavy side, but with a very low offset - we had planned on big flares for this car.

As I was looking at our E36 and how much room we actually had, I started looking around the shop for wheels - and this somewhat neglected E46 project was just sitting there. The wheels had old 315/30R18 BFG Rival-S tires mounted up, which are narrower than the 315/30R18 Yokohama A052s we had in abundance.

After looking at the 3 tires in question side by side, we grabbed a pair of the 18x11's off the E46 and stuck them on the E36 - they fit great with a 20mm spacer at both ends. A nearly perfect fit, and they offered up gobs of brake clearance, even with the "super deep" spoke style on these F14s. To fit the 20mm wheel spacers out back we needed to upgrade from our Vorshlag 75mm long screw-in wheel studs to our 90mm versions. The front already used 90 mm studs.

The front fender opening needed even more trimming to clear these fat 315mm tires at full steering lock. Does that seem too wide of a tire for a 240 hp car that is under 2900 pounds? Well IT AIN'T. We've been running ultra-wide tires on autocross and track cars for 35 years, and we've never made a car SLOWER with wider tires. Not once.

This extra cutting isn't unusual - after adding flares which you had already clearanced for, the first time you drive on WIDE tires, then having to clearance even more. The pictures above are with the overfenders removed and you can see how much had to be cut away - you have to test at full steering lock and cut in front of and behind the tires to allow them to clear - plus the upwards bump travel room, which we already had.

With the overfenders bolted back on, I drove the car outside with all 4 mounted up. Now this is looking better. We might keep these wheels. I took the car on a brief test drive and cornered hard enough to load the old 315/30R18 Rivals.

The Fitment Labs kit has no instructions, none. We looked at images on their website and elsewhere, and had only seen folks mount the fuel door flap in the stock location, recessed 2.5" down in this pocket. I had a better idea - let's move the hinge out onto the overfender, so Christian made a little bracket to do that. The fuel door works great and now, and sits flush with the fender. Still easy to open and fill with fuel, which I did on this test drive.

After the test drive we noticed some rubbing inboard on the rear, so I asked Christian to make some extra EXTRA room with these new brackets on the rear overfenders. Then we slipped in another 5mm of spacer. Heck we can run 18x12" wheels with these tires now, at both ends.

Now that we were sure this set of wheels was going to work, I grabbed some fresher 315/30R18 Yokohama A052 tires that I had used on my 800 hp Mustang TT car in the 2023 season, and we put them on the BMW in January of 2025. These are a full 13" wide, and really should be on 12" wide wheels. This set of tires had already done ten full events on the Mustang, and would go on to do ANOTHER ten events on this BMW (and are still on the car in October 2025!), always making 1.4 - 1.6g lateral. BIG TIRES WORK and on a lighter car like this they LAST a heck of a long time, too.

CHEAP GAUGES + GARMIN CATALYST MOUNT

We have been doing track tests up until this point with the stock gauges and an AiM SOLO, plus a separate video camera, and I have to manually merge the video and data. The Garmin Catalyst is SO much easier to use as it merges data and video on-board - plus the large display shows predictive timing, and you can pop the display out of its mount and look at video immediately after coming off track. We had the Garmin installed at our very first track test, but never got it working that day.

We noted reliability issues with the Garmin + RAM base mount last season, when it was mounted in our 2024 Darkhorse that Amy campaigned in T2 class for 2024. Now that the DH was sold off, and we had time to check out some things, Christian tested the original RAM magnetic mount for the Garmin to use in the M3 - and it works. This meant that the RAM contact plate was broken, and made it flaky to use.

These touch pin inserts aren't available separately, so I had to buy a whole other $100 RAM mount, but I like this holder so much better than the Garmin magnetic mount that we ordered one (sadly not in time to use it at Track Test #3, below). I also wanted the Garmin mounted farther to the right, as it was in the way of additional gauges I wanted to add at the radio spot.

Above right you can see the aluminum bracket that was built to hold the 4-bolt ram base mount for the 1" ball arm, which then grabs the Garmin on the big clip-in mount. The bracket slips in between the (empty) passenger side airbag and the right side vent panel, with bolts that aren't visible. The Garmin needs one USB power port and another USB cable goes to the included video camera, which we mounted to the inside of the windshield. We added a 12V volt meter / dual USB power port on the same bracket to power the Garmin and an AiM SOLO that we will keep on for backup data.

One of the worries we had with this 30 year old engine was oil pressure, and the stock gauge cluster only has an idiot light. Of course we had upgraded the oil pump drive and oil pan baffle, but we still want to SEE pressure readings on track, and ideally coolant and oil temps (we added those two later). With an EFI upgrade coming soon (and potentially a digital dash at some point?) we picked a cheap 0-150 psi "digital analog" gauge and sensor for $36.

Yes, I know that is too cheap to be very good, but we had used this exact brand before on another project and it worked fine. I figured this would work for a stop gap until we figured out if we wanted to drop $2500 on a digital dash. I posted about this project on social media, and a fan of Hellrotten who is local gave us some free parts to use, including the UUC branded aluminum oil filter upper cap with a sensor tap we can use for pressure.

This same guy gave us this single DIN gauge panel, too. After realizing we're not going to be street driving this car much with full aero coming soon, we pulled out the 3.3 pound, single DIN stock radio and installed the triple 50mm gauge mount, with the oil pressure gauge installed.

The image above left shows how the new location for the RAM mounted Garmin Catalyst looks rotated towards the driver, and the oil pressure gauge where the radio used to be. Above right shows a weight check for that same day, Jan 23, 2025 - with 3012 pounds showing 3/4 full tank of fuel, the roll bar, race seats, and big 18x11" wheels and 315mm tires. We need to find some weight to drop... min weight with driver is 2550 pounds with a 3.0L unmodified engine in Max5 class, so the M3 is incredibly overweight.

TRACK TEST #3 - MSR CRESSON - FEB 1, 2025

The first two track tests in this car went "less than smoothly", finally our 3rd track test in our 1995 M3 went off without a hitch.

Temps were perfect (65-69F) on this February 1st member day, and I took 3 stints in the car, spending the first two sessions scrubbing off old rubber on these old but enormous 315/30R18 Yokohama A052 "200TW" tires, testing to make sure the ABS was really fixed, and making damper adjustments.

Then Amy jumped in for a 3 lap stint and threw down a new Personal Best and new fastest lap in the M3 - she obliterated my best lap from the two previous sessions. I both love and hate when she does this - I've been slogging at it all day, working on setup, then she hops in for a 3 lap stint and smokes my time. And we were on a tight schedule, so we didn't have time for another session, and this was the last session of the day.

Lucky for me, she came in fairly early, and I had my gear on - so we hot swapped in pit lane and I went back out in final session for a handful of laps. I had less than 10 minutes before checkers flew.

I got two hot laps before catching two cars that tangled and went off in Little Bend corner, which black flagged the session early. The video linked above shows the two hot laps I took, where I just edged out Amy's best lap by a few tenths. This 1:24.4 lap wasn't exactly the barn burner lap I was hoping for, but we got through this event without a misfire, no tire rub, no ABS failures, or other issues that plagued the previous test events - which was a relief.

continued below

**Fair!** · 10-17-2025, 05:33 PM

continued from above

The lap list below left shows how I hogged the seat time in the car, and the chart at right shows 1.3 g lateral peaks (which ended up being low, as these tires woke up at our next track test).

We were on a tight schedule, as we had to rush over to a shop at the track to get a baseline stock dyno on this car, then load up the trailer, change clothes and head straight to an SCCA awards banquet for the previous TT season (Amy won T2 class and I won Max1 class in 2024). Busy day, but happy enough with the results. We'll be back for another track event here soon.

BASELINE DYNO TESTING - FEB 1, 2025

After pulling off track with a new Personal Best in the M3, we drove over to Rapscallion Motorsports for a baseline dyno pull on their DynoJet 248 chassis dyno. They were super busy but let Amy and me strap the car down and make a dyno pull. Sorry for the crappy audio below - I left my remote mic setup in the trailer, and we were so pressed for time that I just yelled at the camera.

I was hoping for 200-210 whp, and it made 216 whp with SAE correction factor, so that was better than expected for this 100% OEM, 30 year old S50 3.0L engine with fat tires and heavy wheels (doesn't help dyno numbers). I have dyno'd a lot of cars, and normally would make a backup pull or two, but our schedule was super tight. The car was also hot and right off the track. We had some fans on the radiator, but it was by no means a perfect "chilled" dyno pull. Torque numbers were pretty good, too.

This is what this engine needed to make to not be immediately swapped to something else - seriously, if it made less than 200 whp it was getting yanked. But it made the number, and would soon jump up another +30 whp after the exhaust and fuel system changes plus the Link ECU installation. We had hoped to work with Rapscallion on the tune, but their schedule got pretty jammed up so we switched tuners on this car after the EFI install.

LONG TUBE HEADERS & CUSTOM EXHAUST

The 2025 season for Texas Region SCCA Time Trial didn't start until March 29th, but it's already February and we had a HUGE list of things we wanted to tackle before this event. We put in major hours at the shop tackling the big list of upgrades, and it almost went off without a hitch. Almost!

One of the first things I wanted to replace after we finally got this baseline dyno pull was the exhaust. I know from experience that there is some power being choked off with the quiet and heavy stock exhaust. I also wanted to test a theory that we have used on S54 powered E46 M3s and see if the same routing worked as well on the S50.

A few days after the dyno test, we pulled the stock exhaust manifold and heavy after-manifold exhaust and cats. These old bits tipped the scales at 98.3 pounds and would never be reinstalled. Never, ever, EVER!

We had researched E36 headers for a while and settled on this Schmiedmann stainless set of long tube headers. We had also rounded up some cold air intake parts, several mufflers, and a bunch of mandrel bends. The plan was to use dual 2.5" exhaust, merge it pretty far back in the chassis to 3" tubing, then run a 3" rear muffler. We wanted to keep it light and uncork the exhaust flow path as much as possible without making it stupid loud.

I wasn't in love with the Schmiedmann design, as it was made to work with both RHD and LED steering columns, so there was a big dent in both headers to clear the RHD shaft. But it was a fairly well reviewed setup, and didn't try to compromise flow by trying to mate up with the stock after-header exhaust, and also it wasn't some random Chinese made eBay header.

We ordered a bunch of Summit stainless steel 2.25" mandrel bent parts and V-band kits to use to build this exhaust. This was after Vibrant promised a bunch of sponsored exhaust parts - after 6 frustrating weeks of making a list, submitting the sponsorship request, then their excuses, we gave up on them. I wasn't chasing a sponsored deal - Vibrant reached out to me - but I wish I had never fallen for the "sponsored" gimmick. It all just delayed this exhaust system. Above right you can see the janky flanges that BMW uses being cut off of the headers.

Myles installed the Summit 2.25" dia V-band clamps and flanges to the headers, after tack welding them on the car. This will make for a better, leak-free exhaust - I love V-bands.

With the V-bands in place the team of Myles and Austin were able to add bends right past the flanges and turn the twin system towards the rear. These pieces were tack welded in place and seam TIG welded as they went back to the rear.

The merge on this system is really far back on the car, and the guys chopped up the one fancy Vibrant part on this whole system - the dual 2.25" to 3" merge. This was all mounted under the OEM heat shield, which is below the factory 2-piece driveshaft.

Myles made this ovalized section of 3" tubing near the lowest point of the system, snaking under the differential. This leads back to my biggest mistake in ordering - this tiny Magnaflow muffler. I was chasing pounds, and this 6.5 pound muffler looked good on paper. YOWEE it was loud, and was later changed out.

This is what the completed system looked like, above and below. At this point we were pushing up against a deadline - the SCCA TT schedule's March 29th first event of the year. So we had no time to ceramic coat and polish this exhaust - but we did that later. I also wanted to make sure the muffler wasn't too loud (and it was).

All told the exhaust was 27 pounds, with this lighter muffler. This is 55 pounds lighter than the 82 pound stock after-header system. The long tube headers were another 2 pounds lighter than the exhaust manifolds, for a 57 pound savings - and this was also the bulk of our power gains that we would eventually see, too.

CUSTOM COLD AIR INTAKE UPGRADE

I made some mistakes in ordering parts and ended up with a couple of "big" MAF sensors (E39 540i) that we didn't need. We realized later that the Link ECU doesn't need a MAF - like most aftermarket EFI systems it is setup as a speed density airflow measurement system, with a Manifold Absolute Pressure sensor. Oops.

We started with this Bimmerworld 90 deg bend from the stock throttle body to the 3.5" size for the MAF. We substituted a straight piece of 3.5" OD aluminum tubing, then a 45 deg 3.5" silicone bend from Summit.

The sealed airbox is what takes the most time on these custom cold air intake setups, but it is also the most important. I hate seeing a nice build then an air filter just sitting there in the engine bay, sucking hot air from after the radiator. Lazy!

Brad started with a cardboard template in the LF corner of the engine bay, which was then transferred to some .063" thick aluminum sheet. That was cut with flanges to later be bent to mount to the inner fender structure.

A "corner piece" was made to unbolt, which wraps around the 3.5" silicone bend to seal the box off from the engine bay. There is a thick weatherstrip piece that slips over the edges to seal against the hood. We've done a bunch of these and know the short cuts, but it still gobbles up hours to make something that is functionally correct and clean looking. We then painted this airbox satin black.

The two images above show the K&N style pleated and oiled air filter stuffed down into this sealed airbox. This is fed cold air from behind the headlights and not from behind the radiator. The LF remote reservoir from the MCS RR2 sits inside this box as well.

CUSTOM SPLITTER CONSTRUCTION

This was one of the more time consuming splitter designs we have done for an SCCA Max classed car. We wanted to incorporate the "boat tail" leading edge that we used on the 12" extension splitter for my Mustang TT car (Trigger), which was only used for NASA and Apex events - but for this BMW it would be in the shorter 6" extension splitter allowed by Max.

We always start with a check of the rule book, and then strings. This car had no factory undertray pieces left, which is a horrible way to run any track car - but instead of replacing them the year before, I just waited until we had time to tackle aero - which was now.

We are using a furniture grade 12mm thick imported Birch plywood sheet, and Brad started with the rear flange mounting section plus the cutouts for the front tires.

There are a dozen ways to mount the back of a splitter, but we have settled on this simple "shelf" method. We make this style bracket that holds the plywood at the back, and mount this bracket to the subframe. On this car it has some extra bridge sections that tie into the upward curving front subframe, as shown.

Brad cut, bent, and bolted this up and Austin TIG welded the sides - which are what hold the back of the splitter laterally, set the height, and control the rearward movement. The splitter just slides in and out, no hardware or tools needed.

Setting the height of any splitter is a tricky step - we like to keep the bottom 2.5" - 4.0" from the ground. The subframe mounting bracket set the height on this one, which leaves a huge 3" gap to the factory lower lip that will need an air dam. Above right Brad is laying out a single Professional Awesome large splitter tunnel - one we salvaged from my demolished splitter from October 2024, where I slid into a wall in my Mustang at NCM.

The basic shape was done and we took the first of 3 weight checks on this splitter, now at 18.1 pounds. Then it was time to add some weight with the triple thickness front lip. This is an aero trick we proved out on our Mustang splitter and wanted to do here. Using scraps from the same 4x8' sheet of 12mm birch plywood, Brad made 2 more layers of the leading edge, about 3.5" deep from the lip.

These were cut in layers and "glued and screwed" together, as shown. Wood glue and short countersunk screws held each layer to the next, to give the splitter both strength (we needed no aluminum structure) and the fat lip we could then shape.

Each layer was clamped and left overnight, so the glue could setup. Then the next layer was glued and screwed, clamped and let to dry. This takes not just hours, but days - to allow it all to setup properly. This sad hodgepodge of clamps above made me invest in new clamps, because this won't be the last time we do this style.

Once the triple thick leading edge was setup it was time to shape it. Fluids Engineer Jason had a shape he wanted to use again, which comes from the boating world. The theory is that this will help funnel air smoothly under the splitter, for more velocity and thus more downforce. All I know is it takes hours to shape with these hand held sanders - a CNC table would help here, but we have zero desire to make production versions of these.

This close-up shot above left shows the gradual curved leading edge. This isn't just a "hit it with a router bit" sort of thing, as this is nearly 1.5" thick, and NOT a constant radius. We got another weight here and it shows that the fat lip adds (22.7 - 18.1) a full 4.6 pounds of extra weight. At least it is down low?

Now it was time to mark out and cut the openings for the ProA large splitter tunnels. We now place these on the bottom side (as they should be) with a flush mounted cutout using a router. This keeps the splitter plywood as the lowest part of the assembly, which keeps from wearing out the plastic tunnels.

These are attached with countersunk stainless bolts and nuts through the plywood. Total weight here is 22.9 - the tunnels add virtually no weight, and in fact tend to lop off weight, when trading 12mm plywood for plastic tunnels. The 0.2 pounds added is all from the lower air dam bracket and hardware, which is just 1.5" tall garden edging.

ALUMINUM FRONT LOWER CONTROL ARMS

During this whole process we were dropping weight from the interior (see below) I found the Dorman aluminum E30 M3 lower control arms at a good price. So I ordered a set and we replaced the steel 1995 M3 arms, which share the same geometry.

The weight loss (15.7 - 8.5) for the pair totals 7.2 pounds, which is nothing to sneeze at. Not earth shattering weight loss, but every little bit helps.

We have had these on all season without any issues now, so this Dorman replacement is a good upgrade if you need new ball joints and want to drop some weight.

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**Fair!** · 10-17-2025, 06:01 PM

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MOUNTING THE SPLITTER - SIDES AND FRONT

The main splitter plane is built and mounted at the rear, but now is the tricky part - mounting the leading edge of the splitter with Professional Awesome struts. Maybe you have sees splitters online that "don't need struts" or cables, but it is usually a tiny thing. Those little 2-3" extension splitters can get away without leading edge support, but when you are building for Max category rules limits (6" extension) or more, your splitter WILL need struts with a plywood or aluminum splitter.

You then have to tie the tops of the struts to the chassis, at points that are rigid - like a tubular bumper beam or in this case to the factory aluminum bumper. It was only 11.4 pounds, and spans the full width of the chassis - so I decided not to chase a tubular front bumper beam.

Brad said he could get some weight out, and I was game, so he laid out a hole saw pattern and cut the bottom flange only, then reweighed it. The bumper beam lost only 1.0 pounds, so instead of burning another 2+ hours to do the top side, or more time to hole saw the front edge, we stopped while we were behind.

There was still plenty of meat left on the bottom flange of the now lightened bumper beam to anchor all 4 leading edge struts, so Brad reinstalled the bumper cover and installed the splitter at the back so we could game out where to anchor the struts.

Having a full width bumper beam is RARE and this made anchoring all four splitter struts fairly easy. I like hidden upper mounts, for aesthetics and drag, so we chose pathways through the center grill and the two fog light openings. The struts were made to length and now it was time to add the air dam.

MAKING THE AIR DAM

That 3" gap between the bottom of the factory front lip to the top of the splitter needs to be bridged, and to do that we use 1/8" thick textured ABS plastic sheet. We have that overlap the bottom of the factory bumper cover, but the air dam still needs to be mounted to a lower bracket.

This garden edging is a great hack that we saw some other folks do online, and we adopted this here at Vorshlag about 2 years ago - much easier than making full width, curved, custom aluminum brackets. It is plenty strong, and I found this stuff in 20' rolls at Home Depot - click the image above right to see more details on the box.

I missed some of the steps on our E36 air dam install, as so much was going on in the shop at that time. So I've substituted some shots of the garden edging and air dam being installed to a splitter we did on a BMW Z4M without tunnels (NASA TT4 doesn't allow them) in October 2025, above and below. The garden edging is laid out in line with the bottom of the bumper cover, where the air dam is mounted. We use stainless M6 x 25mm countersunk bolts from the bottom of the plywood, through the edging, and M6 nylock nuts on top. It is time consuming to drill and countersink these holes, but you only have to do it once...

The images above are once again from the Z4M splitter. Above left you can see a small piece of wood used as a drilling height gauge, with hole spacing measured out and marked on blue tape with Sharpie lines. The above right image is of the pneumatic riveter installing the enlarged head, black aluminum pop rivets, which attach the 1/8" thick ABS to the garden edging brackets.

This air dam section stays on the splitter and floats tight against the factory lower lip and body. Don't forget to allow for some overlap, like 1/2" more than you think. This allows the splitter's Angle of Attack to be adjusted - you want to go as low as possible without scraping. A 1-2 deg down angle is great, and worst case it is level with the ground plane.

Here's our E36 splitter again - above left shows some aluminum bracketry added to tie into some mating brackets on the chassis. We need this to secure the splitter fore-aft, even with the front struts. Sometimes we can get away with less structure, but this E36 is pretty lean on structure at the bumper cover. Above right shows the completed air dam - now it all has to come apart for primer and paint.

SPLITTER PAINT AND CLEANUP

The normal process we use for painting a splitter is two coats of Rustoleum enamel in Satin Black. This stuff isn't cheap, but it water proofs the plywood and looks great. Each layer needs 4-6 hours to dry, and that soaks up 2 days, minimum. So this time we used some Latex KILZ primer paint for the first layer, which is cheaper and dries faster.

After taking off all of the air dam bits and tunnels, Brad sanded all of the surfaces of this splitter, cleaned it, and laid down a coat of the white Kilz.

With the primer on it only took one coat of the black Enamel on each side to look great. Again, this coat has to sit for 4-6 hours, then we can flip it over on the stand and paint the other side. Brad uses a foam roller on a 3" or 4" roller for these, then throw away the roller after each coat (or bag it in plastic and put in the freezer, for use on the next coat).

These two images show the the finished splitter after paint and reassembly with the tunnels and air dam parts. We also have the lower anchors installed, with two titanium skid pucks from ProA installed at the center two strut mounts on the bottom. All in the assembly is 26.0 pounds, after starting with an 18.1 pound "bare" splitter without the tunnels, boat tail leading edge, air dam or hardware. 26 pounds is pretty light compared to aluminum splitters we have done in the past.

Installation is pretty simple: you slide the back of the splitter into the rear mounting bracket, then hook up the four struts at the front, and two bolts on the side. This thing is now rock solid, and you can stand on it. Amy's driven all season with this, even crashed over a curb with the left front, and it is still going strong.

And while this is normally where people stop, we have some unfinished business on the outer edges - you can see a TON of the front tire poking past the front bumper cover, and we want to clean that up. We've done tire spats in the past, but since SCCA TT Max classes allow "up to two canards" per side, we made that happen.

BOXING IN THE RADIATOR DUCTING

Normally the factory undertray and some other plastic bits do a good job of forcing air from the front grill opening through the radiator - our car had none of the lower plastics, so we made this lower box section to duct the front of the radiator. This was done to prevent any air spilling around the radiator.

Brad made a simple pattern that resembles the factory plastics, and tied that into the grill opening, and it now seals to the radiator. It bolts in place and hides above the splitter now.

PAINTED & POWDER COATED PARTS ARRIVE

We had taken the overfenders and sunroof from Fitment Labs off after fitting those to the M3 weeks earlier, and our friends at Heritage Collision got these painted in the factory Hellrot red color - color matched off of the fuel filler door.

I really didn't want the car to compete at its first TT event with the ugly 2 color red / white mismatch, and Shiloh and his guys got the paint matched really well. The car's 30 year body is a little faded, but Brad buffed the rest of the car out to match. We'll take the chassis back to Heritage and have them shoot the hood, trunk, doors and roof after this 2025 season. We might get some carbon bits (hood, trunk, doors) to try to save some pounds, we will see.

The guys got the painted overfenders bolted back onto the formerly ratty looking M3 and WOW what a difference. This was a much needed upgrade before the season began!

This is where the sunroof was reinstalled (showed it earlier) with the seal around the edge, and the rear overfenders bolted on with our extension brackets.

We also took the rear trunk bulkhead made last year to our powder coater and had it sprayed with semi-flat black, which tidied up the back seat area. 1/8" thick x 1" wide foam weatherstrip seal around the perimeter for an air tight seal. I've got some interior work to show below, which includes the black carpet you see above right.

SPLITTER END TREATMENTS

If you know anything about aero drag you will notice that the front tires stick out past the (very trimmed) front bumper cover - sticking out in the air steam, spinning and churning up the airflow along the sides of the car. We want to clean this up if possible (tire spats), or better yet - put it to work (canards)!

We chose an end treatment similar to what we have on my Mustang, a pair of aluminum canards on each side, but with an outer barge board to hold them together and trap some airflow that would otherwise spill off the sides of the splitter. I started with some cardboard and made very crude template versions to start with.

Myles and Brad cleaned up my gross first draft (above left) and made more aggressive canards (above right), all while engineer Jason was on vacation. We sent him images as the cardboard templates progressed and eventually got his blessing.

The canards were made in aluminum, and have a slight curve - I'd wish it was more, but this is what we could do within the tight time constraints we had. These have tabs that bolt to the bumper cover, as seen above left.

Then the outer "barge boards" or splitter end plates were made, which curve around at the top with a 90 deg angle and tie into the body under the headlight trim panel. The bottoms of the vertical panels actually float above the splitter with a small air gap, and they are mostly there hold the outer edges of the canards in place.

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**Fair!** · 10-17-2025, 06:09 PM

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These side aero pieces tie into the headlight trim panel as shown above left, and you can see the additional front bumper cover structure added to tie into the sides of the splitter. Myles took the formed aluminum canards and tack welded them to the outer barge boards.

These were then finish TIG welded on the mobile fab table, the the whole structure was bolted to the bumper cover - it can come off as an assembly with the front cover, if needed. This was all done in a major time crunch.

REAR FENDER "TIRE SPATS"

Similar to the front tires, the 315mm wide rear tires stuck out past the overfenders and into the air stream. Not as critical to drag as the fronts, but still important to reduce rear tire drag (underside "tire squirt" will be addressed later). It also filled in a gap in the widebody kit that I felt it needed. I cut a paper version of this for Christian, then he made a proper cardboard template that he transferred into red "race roll" material.

The spats blend into the bodywork behind the front doors and gradually curve out to cover the rear tires. The race roll was cut to match the cardboard template and a 90 deg bend was put in the bottom - yes, it bends with the box and pan break. Tabs are on the trailing edges to tie into an aluminum panel to seal it all up.

The tire spat was held in place with Clecos while Christian made the cardboard template for the rear panel. The bottom overlaps the body and it is all riveted in place. The above right pic shows the completed tire spat riveted in place with the aluminum rear panel. A heat gun was used to smooth the curves in this panel, and its almost car show worthy, and better than we see on most race cars.

RTD SHIFTER UPGRADE (AND MY SMALL MISTAKE)

I hate the stock body mounted shifters on every BMWs ever made. They are trash, and have wear items that make them even less vague. The mounting onto the body, coupled with worn engine mounts, leads to the dreaded "money shift": where you try to downshift while the car is loaded laterally, nothing lines up right, and you end up going from 4th to 1st. Then the engine over-revs and usually explodes.

I drove a customers BMW with the CAE shifter, and it shifted SO MUCH BETTER that I almost dropped the (at the time) $1200 for one. Today it is a $1500 shifter, which is more than the transmission is worth!

There are several similar options and I had been trying to buy an RTD shifter for weeks, but kept running into issues with payment issues (they are in Lebanon). These are 1/3rd the cost of the CAE, but I couldn't get one. I saw one pop up on one of the FB groups I manage and bought it for $250. It was raw aluminum and came with a shortened lower shift arm (DSSV).

Being a pimp I couldn't leave it raw and had the shifter handle and knob anodized with some of the CNC machined parts we make. Most were black hard anodized expect the knob, which is red. That was the mistake - according to the owner of RTD (we've chatted many times now): this was an older unit, and the plating thickness we added wrecked the tolerances.

At the first TT event Amy had a lot of issues shifting, and I so did I when I made some laps. We came back to the shop and Myles cleaned off some of the anodized coating where some parts meet, then it was adjusted, and now it shifts PERFECTLY. In retrospect I should have tried another payment method and bought a new RTD one, which would have come coated in the newer design, and we would have avoided the shifting issues that I created.

NINE LIVES REAR WING INSTALL

Back in January we measured the width of the E36 to see what the maximum width we could use. SCCA Time Trial Max category includes mirrors, so we measured that at 72.5" wide. We then ordered the 71" wide "big wang" kit, which is a bolt on.

For most of our shop builds we just buy a bare wing element and make the uprights, but we had such a huge list of mods ahead of us we opted to just buy the kit and use it as-is.

Nobody ever weighs things - but we do! When the wing kit arrived I assembled the endplates and weighed the wing (12.

, then added the upright mounts and hardware (17.6). The 5.2 pound fiberglass factory piece was removed, so it was only a 12.4 pounds added. Would a carbon wing weigh less? Yes, by about 6 pounds, but at 4x the price. How much is 6 pounds worth?

There aren't installation instructions but it isn't rocket science. We marked the trunk with tape, measured out the centerline, then mocked up the assembled uprights and wing to mark the mounting holes. These were drilled through the entire trunk. The steel trunk is STRONG and you need no reinforcement, especially since the mounts also pick up the vertical face.

We had some slight mismatched on our install so Brad made some shims out of black Delrin, which he sanded at an angle to fill the gaps at the body. You'd never know these were behind the uprights if I didn't show it.

We set the AoA at a modest level - I haven't actually adjusted the angle of this wing, as it just balanced out aero front and rear perfectly on the first try. Dumb luck or mad skillz? You decide!

TWO MORE GAUGES ADDED

With the Link ECU work going and after deciding against a $2800 digital dash, we needed a way to see more data - with old school gauges. I doubled down on the same import gauges we had added for oil pressure.

One shows coolant temp, with a 38mm inline hose adapter for that. The other is oil temp, which we added to the UUC filter cover with an 1/8" NPT threaded hole.

The included wiring was run from the sensors to the dash area. The coolant temp sensor was spliced into the upper radiator hose after the thermostat, but it is a better than the numberless 1/4 sweep factory gauge.

The gauge panel we had before with the single oil pressure gauge needed to grow, and instead of just slapping the 2 other gauges in there I wanted a full panel for additional switches and another USB port. So the guys made a cardboard template, which I scanned and then they turned it into CAD and then a CNC cut panel from .080" thick aluminum.

A secondary bracket was added that bolts to the panel, shown above left, to give it strength for the RAM mount we were about to add. The aluminum panel was brush finished and the included tabs were bent 90 deg, and the curve of the dash was bent into the top portion. This was fitted in place of the radio and upper vent, then the rocker switches were added - one can work for the cool suit, and the other controls our electric defroster, which I will show below. We wanted to move the mount for the Garmin Catalyst display here with a RAM mount, closer to the driver, so we left room for that.

The panel was shot with satin black paint and then bolted in with the 3 gauges and USB port, plus the relocated RAM mount. Where we had the Garmin mounted way over above the glove box was too far out of the driver's line of sight to be useful for predictive timing. Best laid plans often do not survive the first lap on track. This setup has remained all year - but I still mount an AiM SOLO off to the side to gather more data - which I've started merging with the Garmin video for better in-car videos.

DROPPING SOME WEIGHT

This is a HUGE section of work that spanned months, from January through March. I'm going to hit the highlights here, but many hours were spent chasing 100 pounds of weight loss from the interior nad engine bay.

Lots of factory bits came off and never went back on that I didn't weigh, as work happened on so many systems so quickly. The factory airbox, MAF sensor, cruise control and a bunch of emissions stuff left, as did the electric fan that normally is triggered when the A/C is engage. Yes, the A/C left for good.

The radio was already removed (3.3 pounds) but these speakers and amp also came out (6.1). The factory fog lights were 2.8 pounds and served no use for us on this semi-dedicated race car (with an interior).

With the 4-point roll bar our 1995 M3 is considered "Level 2 Safety", so we can remove any interior bits behind the roll bar - like the back seats, rear interior panels, and we did. We have to keep carpet, headliner, and interior panels ahead of that - but they can be REPLACED with alternate (read: lighter) materials. We planned to exploit the heck out of this without getting into any gray areas.

What about HVAC? How much is required to stay with Level 2 Safety? The rules were not explicit, so I wrote a letter to the TT Rules Board (linked here) asking for a clarification. And this is what was amended to the rules via FasTrack.

I received an indirect answer from a member of the TT Board, which brought some clarity on the bare minimum interior HVAC item basics needed for Max: a heater

This was the official response which came a few weeks later, but we had already started down the "light interior" rabbit hole by then. Way way down...

This began with a desire to remove the factory carpet and insulation, and to do that properly you have to remove the entire dash in most BMWs. That is a process but there was some juicy pounds BEHIND that dash I wanted to mine as well. So while Brad was working on the splitter, Christian dug into the interior weight loss program - starting with the dash.

By the rules even with Level 3 safety (we only have Level 2 on this car) we have to keep the dash, so the 11.5 pound stock unit is staying, as well as the 8.6 pounds of rusty steel structure that holes it in place. Compared to newer cars this is all pretty dang light.

What we wanted to lose first was the HVAC box, shown above, hiding behind the dash mounting structure. This bulky mess holds the squirrel fan, heater core, and A/C evaporator core, and those bits along with the ducting totaled 17.6 pounds. Newer cars get closer to 25-30 pounds, but we'll take it - and chuck it all out.

The factory carpets in some later BMWs weighs 70+ pounds, and I had hoped this insulated, deep shag, wool carpet would weigh more - nope, just 40.3 pounds. But there was even more weight to be saved in the floors.

There was 29 pounds of sound insulation on the floor and firewall that Christian pulled that out with a heat gun and putty knife, which takes time to do cleanly. Yes, we know about the dry ice method - trust me, this does NOT work on all cars, esp. the German cars. Heat gun and patience works wonders. 29 pounds is no joke!

In place of the HVAC box we now had a huge hole in the firewall, which we replaced with a custom panel made from .063" thick aluminum - bent to shape and sealed with 1/8" x 1" wide weatherstrip. Four rivnuts mimic the mounting and bolts it in from the engine side.

After buying some crap from Amazon that turned out to be felt, I went to the Racers Depot and bought a big roll of the cheapest black carpet sold (Home Depot) to cover the floors. It was $.89 per square foot and I think I spent like $30, with lots of extra. Its actually pretty nice for a "race car", and meets the letter of the rules.

We saved another 25.5 pounds in interior plastics and panels that we legally removed from the back seat area (and the glove box, which we put back in temporarily), and ended up needing only 5.9 pounds of the black carpet to cover the floors. That means our replacement carpet alone saved 34.4 pounds - we're starting to make some real gains here, all while keeping the legal required interior in our race car.

And this is real, legit carpet - not felt but something you would use on a speaker box or some other interior. It presents nicely and nobody will confuse it for anything but carpet. Christian has done interior work and he measured and hand cut this from our $30 roll to cover not only the area ahead of the roll bar but even covered the back seat area, which we didn't technically need to do (but I want it to look nice, so damn the 2 pounds).

I felt that the dash support tubular structure was 100% necessary, but I couldn't stand even knowing that this bare, rusty steel would be behind the dash. So we primed and painted it black, and nobody will ever know except you readers! That was bolted back in place so that the dash cover could go back in place, as well as the center control - after we installed the new replacement carpets.

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**Fair!** · 10-17-2025, 06:11 PM

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Lots of 30 year old rubber hoses that dealt with the heater core were also removed, which prevents untold number of potential leaks down the road. You can totally tell that Christian was having fun re-routing and removing these! The intake manifold had to come off to get to everything, but now we have no factory heater - so how do we remain class complaint??

One result from the answer to my TTB question - all we need is a heater, so we ditched the rest of the factory HVAC (a bit of weight) and I bought this 800 Watt electric heater / defroster. It weighs 1.8 pounds and meets the rules for a heater to the letter.

We tested this, and sure enough, it pumps out some HEAT - with multiple electrical elements and a fan, but it does draw some amps. Just like with your regular heater, we will want to make sure the engine is before we flip that switch.

The carpet goes to the firewall over the tunnel and on top of this is a custom bracket was made to mount the electric heater. That is plumbed with two ducting hoses up to the defroster vents in the dash. So if the windshield gets frosty we can flip a switch and heat things up. The rest of the interior went back together at this point - the headliner was also installed, but I will show that below.

Adding the electric heater with a blower motor meets the rules, and having no radio, no speakers, and no air con is confirmed to be legal for the Max class Level 2 Safety. We saved a chunk of weight doing this work over the course of about 10 weeks. Not a small task, to be sure, but we're EXTREMELY overweight for this class and needed to find some real pounds. We're still too heavy, but now less so.

HEADLINER, A/B PILLARS, & REAR DECK PANEL RECOVERED

In my 2001 BMW 330Ci E46 coupe I built for SCCA Solo DSP class (2 pics below), to ditch the sunroof I had to change out the whole roof steel panel and import a factory "no sunroof" headliner from Germany (these two parts were $1400 of materials in 2009!) This was a ton of work and you can see the steps in this gallery.

SCCA Solo Street Prepared has some ridiculous rules, and it is dying a slow death, as the Street Touring and Extreme Street categories slowly dwindle its numbers. Luckily we have a much more sensible ruleset in SCCA Time Trial - we can just put in a sunroof delete panel. A $200 / 2 hour fix instead of a 25+ hour nightmare job.

When we removed the sunroof on our E36 M3, we had no delete kit on hand. We finally replaced it with the panel from Fitment Labs, but left the headliner out for testing. To be SCCA TT legal, we needed an interior covering from the roll bar forward. We could have glued some fabric over that portion of the roof (ghetto) but I want this to look nice. We modified the original headliner panel and just filled the hole from the sunroof and upper control panel with two pieces of 1/8" thick press board - that was epoxied in place and allowed to set for 24 hours with steel weights applied.

To recover the headliner panel - and the other panels shown below - I picked up several yards of black faux suede or microsuede. Amy and I recovered the headliner in our 1997 M3 a decade ago with this stuff and it looks GREAT and the price isn't terrible.

3M headliner adhesive is sprayed on the (very clean) headliner and back of the material and allowed to tack up for about 15 minutes. Then you apply it in stages, working it into the contours and stretch and pull and get it to lay down before it sets up. There are too many tricks to show on this forum post, but Christian needed no help, as his previous interior skills came into play. I liked the result so much I had him recover the rear shelf, with covers added where the speakers used to be.

The A- and B-pillar material was all falling off after 30 years, so they were stripped and cleaned, then recovered as well. All of this came out SO NICE, it is just hard to show in pictures.

The headliner looks amazing and with the grab handles and sun shades back in place it looks like a show car, at least these panels. If you are ever at an event where we have this car, ask me to see the inside, and touch the headliner material. It is downright luxurious! We've since done this same material in our 2004 BMW 330i ZHP we have for sale, and everything above the bottom of the windows is covered in this micro suede. It looks crazy good!

We were almost done in our Level 2 Safety interior mods - but we needed one more small addition, just for driver comfort.

FALSE FLOOR BUILT FOR DRIVER'S SIDE

After the seats were back in the floor felt... weird. Where there used to be inches of thick heavy foam insulation and wiring raceway covers, there was just nothing, and the floor had a huge step in it that dropped off to driver's left. So it was time to build a false floor to raise things up for your feet and make it feel right when working the pedals.

A cardboard template was made and tweaked then this became .080" thick aluminum sheet with ribs and sides to fill in the missing 2.5" to 5" of gap that the foam used to take up.

You can see how tall this false floor box is and how uneven the heights are above. This is to level the very uneven factory floor. Christian made this and of course I asked him to add dimple die holes - to both drop weight and add strength from the cold worked flanges. After cutting the holes but before the dies were smashed over them he brushed the top of the panel with the burnishing wheel.

The final structure weighed in at only 2.4 pounds and is rock solid. A bit of grip tape was added laterally to keep the carpet from slipping. It is all hidden under the carpet and driving no longer feels "weird" with the missing foam over the funky shaped floor.

I would say that our Max5 1995 BMW M3 has a complete interior and it is 100% beyond reproach, and visually includes more items than many other Level 2 Safety prepped Max entries we have seen at Time Trial Nationals. It has a full dash with no gaping holes. A full interior ahead of the roll bar, and recovered rear deck, A- and B-pillar panels, and the full length headliner. An aftermarket carpet covers all areas of the floor required. And a functional heater / defroster is in place.

NOCO LIGHTWEIGHT BATTERY INSTALL

I have hesitated for years to jump on the lightweight Lithium battery bandwagon. We had such bad luck with AGM batteries with a rash of 9 new units failing within months of installation, from two brands in 7 cars. But I finally took the leap in 2025 to an AGM on this car.

I looked at these two highly rated NOCO Lithium Iron Phosphate units (LiFePO₄ or LFP), and ultimately chose the 4.0 pound NLP20 for the M3. It has 600 cranking amps. I've since switched to buying the NLP30 for several other race car installs - these are exactly 5.0 pounds and have 700 cranking amps. The extra pound is worth the extra oomph.

We already had a fairly lightweight and perfectly effective 28.3 pound wet cell lead acid battery, which is smaller than the OEM size. Our custom battery tray and billet hold down were unmodified to work with the NOCO NLP20, luckily.

If you didn't know what to look for in this truck you might not notice it, but the 24.3 pound drop well was worth the $179 price. These are not idiot proof, of course, but we've learned to leave them on a NOCO smart battery tender. I would hesitate to use one in a daily driver, honestly.

We had a learning curve and swapped the wet cell back in for half the season, but we have the NOCO back in this car and several others now. I have been bringing a NOCO battery jump box with me to the track for the last 2 years, and it serves as a backup if we do something dumb and leave an electrical system on for hours with the engine shut off at an event.

A WEIGHT CHECK AND OUTSIDE PICS

We did the weight check on March 21st, 2025 and I was pleasantly surprised to see the 2833 pound number - down from 3013 pounds a couple of months before (a solid 180 pound drop). This was right before the 9LR wing kit arrived, but we know what the wing weighs (17.6 with uprights), and the rear tire spats and front splitter end treatment don't add more than 5 pounds. So we're under 2850 pounds (still with 3/4 tank of fuel) at our first competition Time Trial event on March 29th.

The pictures below happened 4 days later than the weight check above - after the front canards , rear wing and rear tire spats were added. This last few aero tasks happened so fast I cannot describe what a thrash the whole crew put into those 4 days!

Right after shooting these outside pictures the M3 went into the trailer and I towed it out to G-Speed to have the Link ECU tuned.

That tune did not go great, as the stock 1995 17 #/hr fuel injectors were NOT up to the task of the extra power that was unlocked with the exhaust and intake changes. Jon the tuner had to restrict RPMs to 5500 rpm to keep it from leaning out. The injectors were at 100% duty cycle by that point, and Amy had to limp it through the first Time Trial event, short shifting it everywhere - with a shifter that was fighting her. A real challenge!

LINK ECU PLUG-IN EFI UPGRADE

Back in October 2024, a buddy stopped by the shop to talk about the company he was working for - Link ECU. I've known George Lowe for over ten years and he lives not far from our shop. We discussed EFI options for a number of vehicles in the shop, and this OBDI, S50 powered E36 would be the first of 3 shop cars we have put Link ECU on.

George showed us this system **** that is made for the OBD-I BMW E36, which is a Link G4X "plug and play" aftermarket ECU that works with the stock engine harness. There's reasons why they only do these for some cars, and luckily we had a 1995 model M3 - the only US market E36 M3 that works with their system (some folk change to OBD-I harnesses in later E36s to use this system).

Their system is made to work inside the stock DME housing. So when we got started with the swap, Brad pulled the stock DME from this pocket in the firewall, on the right rear of the engine bay. It was nasty in there but relatively sealed up, and the unit was removed, cleaned, and opened up. There was an old Dinan EPROM chip in there, ha! Somebody had "tuned" this back in the day - but the rest of the car was bone stock. What a waste...

Once the Link ECU was installed into the stock enclosure, Brad modified the housing to allow for the vacuum line and additional inputs / outputs to pass through the case with weather tight grommets. This included some additional sensors and the Wideband O₂ sensor (Lambda CAN module), which they strongly suggest for racing.

Brad mounted the Lambda module behind the plastic firewall cover, and the new Link installed enclosure went back into the (now clean) opening in the firewall before be covered up.

It looks a little crazy above, as there was some additional wiring added for optional sensors. Brad added heat shrink and braided harness coverings to all of the wires and it took about 2 days to do this whole install - a fraction of the time it takes to do a stand-alone EFI system with a whole new harness, plus it has a huge cost savings.

During this same time period, Christian did a "dual fuel pump" upgrade to the fuel tank. Trust me, just buy the Bimmerworld kit, because we chased our butts a little here. We got it to work with out home-brew kit here, but the way we routed the fuel line to go from one pump to the other saddle keeps hanging up the fuel level sensor, and we've finally about to fix this in October 2025. Again, buy the BW kit and save these hassles. Cheap people pay twice! (*me)

With the new computer and wiring tucked away, a start-up tune from Jon at G-Speed got us going and the engine fire up without any drama on March 21st, and we had the car to G-Speed to tune later that day.

WHAT'S NEXT?

Well that massive amount of work took way too long to cover properly, but this may be the most intense amount of work we do to this car for the next 2 years, and I felt like we needed to get into the details. The tune was not without some drama, from an old fuel cover seal that was leaking at full tank levels.

Next time I will cover the first tune and subsequent SCCA Time Trial, which was a bit of a mess, due to fuel injector flow. Luckily Amy was able to squeak away with the win, with a handicapped tune. We came back in April and fired the money gun to replace the ENTIRE fuel system, injectors, and more. Then another tune that unleashed the extra RPMs that were held back due to the lack of flow from the stock injectors. That's when the car REALLY picked up some time.

Thanks for reading!

Terry at Vorshlag

Announcement

Vorshlag BMW E36 Development + Project Hellrotten

Vorshlag BMW E36 Development + Project Hellrotten

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