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  • Fair!
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    Re: Vorshlag BRZ/FRS Project Development Thread

    Project update for January 11, 2019: We had a crazy 2018 and that delayed many of our plans with this project. But after a lot of delays, some tangents developing and testing on this car with the brakes/suspension/flares/wheels, and lots of track... it is finally time.


    The mock-up LS engine + T56 Magnum XL 6-speed in our FR-S as of 1/9/2019

    The Subaru 2.0L has been removed and we have finally begun the V8 swap on Amy's FR-S! This work began in December 2018, with work to be done in spurts between billable customer work. As we continue with this swap we will try to better document every step of the installation as well as develop more solutions along the way that apply to street cars and track-only builds alike.



    In this update we will cover some steps of the LS swap in detail, which we intend to be part of the instructions for the 86 V8 swap. This time this includes: removal of the stock drivetrain, modifications to the stock transmission tunnel, removal of two plates from the front crossmember, and an optional step for replacing the stock crossmember with a stitch welded/reinforced version.



    We also show some of the random repairs and upgrades to our 2013 FR-S during this swap, like a carbon front nose, wheel bearing replacement, final fab work associated with the flares we added last time, an over-the-top Holley Hi-Ram intake mockup, and some weight analysis of our car from when we bought it in 2016 to where it was right before this V8 swap in late 2018. Lots to cover, let's get started!

    WHEEL BEARING REPLACEMENT + ANALYSIS

    At the August 25th, 2018 "double header" track event, where Amy and I both tracked it on the MSR 1.7 and I also ran it that day in the SCCA Time Trial on the MSR 1.3, I smoked a right front wheel bearing. Loud howling noises, visible movement when the car was raised, dead. Not a bit deal to replace.



    In September I looked for a replacement. Prices ranged from $85-180 for a front wheel hub assembly, and I picked the Timken (a brand I trust) version for $95.



    Brad pushed out the stock length wheel studs and installed our longer M12 studs into the new bearing flange, then bolted the assembly in place. The brakes went back on and with a wheel installed, it spun smoothly with no slop in the bearing. Fixed.



    This video above shows this all in just over one minute.



    Now the question is why did this part fail right after installing the 315mm tires? We have tracked this car so many times on the stock sized tires, so why now? Was it the 100mm wider tires loading the stock wheel bearing too much? Did the use of a big brake kit for two years with ZERO brake cooling "cook" the wheel bearing over time? Or was it just from this being a car we bought with a few known issues (bent wheel, bent control arm, etc) that was finally wearing out a wheel bearing at 88K miles? These things do wear.



    I am a little worried about this long term, and Jason has researched larger wheel bearing options - but they involve switching out uprights, new wheel bolt patters, and more work we want to avoid right now. I want to get the V8 in the car as quickly as possible and then start track testing, to see what else breaks with 600+ whp.


    Left: S550 Mustang brake cooling backing plate. Right: 2018-19 Mustang front inlet ducts

    To remove one of the variables from this potential issue we will design a series of brake cooling backing plates (for both the OEM front brake + this 330mm Powerbrake) and front inlet ducts for the 86 chassis, and run these with 3" or 4" hoses in between. Forced brake rotor cooling tends to also cool the front wheel hubs, when tends to extend their life in other cars by leaps and bounds. We will do this before our next test, and keep an eye on front wheel bearing wear.

    FINAL FLARE CHASSIS FAB WORK

    In my last post we had tracked the car with the giant tires after doing the bare minimum of fab work necessary to clear the tires and flares. But we left some work un-done. The frame end we had to cut needed to be "capped" up front, plus some sort of fender liner needed to be added back. In the rear the tacked together "pie cuts" needed to be fully welded, sealed, primed and painted.



    We had a deadline to meet, and again - we only get to work on shop owned cars when we have a gap in scheduled customer work. So in November I tasked Evan to go back and tackle the final fab work necessary to "finish" the flare job. It was all welding and metal work.



    The factory frame pieces cut off were used as a template, transferred to a DXF file, and cut on our CNC plasma table in 18 gauge steel. These were then welded in place with a series of MIG tack welds.



    The welds were ground smooth and the aras masked and painted with zinc based self-etching primer.



    Then seam sealer was applied to make sure these welded seams were water tight.



    Fender liners were next. I had Evan cut the rear 1/3rd off the OEM plastic bits and that seems to fit without rubbing the 315mm tires. We will address the back section later with some custom inner liners made of plastic or thin sheet aluminum.



    Out back it was just hours and hours of cleaning up the gaps between the pie cut metal that was moved upwards to clear the taller/wider tire in bump direction.



    Then primer and seam sealer on all of the bare sheet metal. Then the flares were bolted back on and the car was handed over to Amy to be street driven again.



    INITIAL WEIGHT CHECK & ANALYSIS

    As you have known Vorshlag to do on all projects, we are going to try to weigh more bits and pieces that come off this car as the build progresses. And a BEFORE weight is critical at the beginning of a project is as important as the AFTER weight.



    The weight above was from August 23, 2016 in bone stock form, with the spare wheel/tire and floor jack removed, and almost zero fuel. We do this for almost every car, and call this our "race weight". Which is the race weight (without driver) you could autocross or track the car at. And while some cars need a bit more fuel to prevent starvation, a "no fuel" weight is a good way to compare to other cars.



    This was the weight on December 11, 2018. The car had more fuel this time (1/4 tank), and we had upgraded from the comically small OEM wheels (17x7) and tires (215mm) to the Forgestar 18x11" wheels and 315mm Rival-S tires. We might need to go wider out back with the V8 we have planned, but it will be a safer baseline to start with than the 215mm Prius tires. This also has the Powerbrake 330mm front kit, a giant Optima battery out back, and Whiteline coilovers + camber plates.



    Somehow the car gained 84 pounds in the past 2.5 years. Again, probably 25 pounds of that is fuel. The Group 78 Optima Red Top battery is massive, and moving it to the back requires 10' of big 00 copper wire as well. The flares and fab work added some weight, the brakes and coilovers tend to lose a little, so wheels and tires are the bulk of the rest of the difference. Seeing that they are 4" wider per corner, so that is to be expected. Still pretty light starting weight at 2718 lbs (high 2600s without fuel).



    Should I worry about 60 pounds added with all of these updates? Probably not, but I am a little obsessed about weight. This car is still almost 1000 pounds lighter than my 2018 Mustang GT, which I race at 3855 lbs with driver and fuel. The FR-S has the same track width, and will soon have 150-200 more horsepower, too.

    continued below

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above




    Left: Entering "Rattlesnake" at T10. Right: Entering "Wagon Wheel" (T1) shows loaded outside camber again

    Tire height changes change final gearing, but the taller 315mm tires (25.5" tall on the 315/30/18 vs 24.7" tall on the 215/45/17 Firestones) actually helped in the "rattlesnake" section of switchback turns (T9 to T1). Before, on the shorter tires (which made for "shorter" gearing), I could only downshift briefly to 2nd gear at T10 then had to buzz back up to 3rd gear before T11, to avoid an over-rev. With the 315s I could use 2nd gear from the end of T9 all the way through T1, and it helped pull out of "Wagon Wheel" (T1) with more of the meat of the FA20's powerband. And 3rd gear worked better in Turns T5 - T7. So taller tires don't always hurt you... sometimes they help. Taller final gearing often means less shifting, which can save time in some instances, too.



    Amy ran her quickest times ever in the FR-S after I coached her for one session ("Don't lift!!") and had a blast. Nobody doesn't like LOTS of grip! The tires saw minimal tire wear after her 2 full sessions + my full 30 minute session on the 1.7 or another 3 full sessions I ran on the 1.3. Gotta love massive 200 treadwear street tires on a light car.

    SCCA CLUB TRIALS ON MSR-C 1.3

    As an instructor for the Club Trials group I could ride with anyone, run in any run group, and take passengers - so that was worthwhile.


    These MSR 1.3 event pics were purchased from Lightspeed Images

    Most people ran their best laps in session 1 or 2 but I ran the same damn lap time in all 3 sessions on the 1.3 mile course: 1:10.0, 1:10.1, and 1:10.3. Lots of traffic, not easy to pass, but I always got a clear lap in every session. It had been almost 10 years since I had run the MSR 1.3 mile course by itself so I was a little rusty, but came out swinging and was quick early on. Lots of people got faster throughout the day where I did not - which is typical for me.



    I could not get my AiM SOLO data logger and lap timer to work on this 1.3 mile track (course wasn't loaded in memory) and that really hurt me. I literally NEVER drive on track without my predictive lap timer. This device shows me in real time where I am finding or losing time, corner by corner, lap after lap. So I was driving blind, and wasn't able to find the time that was in the car. I was slower than one STX BRZ, which is frustrating. A lot of these SCCA folks have run the 1.3 recently, but I wasn't really able to learn it like I usually do with the predictive timer.



    I could go into T1 and T2 nearly flat out, where others had to brake a lot, and if some folks people tried to follow my line/speeds through those turns... wee! ...only to find themselves far off the line. I was able to have some fun lead-follow laps with some of the faster cars, but two of those went off track trying to keep up (or stay ahead) with the insane cornering power of this little 86 on 315mm tires - a BMW 1M and Cayman S - but they luckily didn't have any damage.



    The fastest car on the 1.3 mile course was Feras (above left), who's black C6 Z06 has brakes and other work from Vorshlag and a 468" LS7 from HPR, with a 1:03.338. The 3rd fastest was Scottish Joe's blue C7 Grand Sport (above right), which we have also worked on, with a 1:04.757 (see the 1.7 MSR test lap in this car in my list below). Lots of people showed up for a hot day but had fun, with 37 cars posting times.



    Vorshlag sponsored the after party that lasted nearly 2 hours, where the group wiped out the cooler. Plenty of good bench racing. For Amy and I, after 3.5 months of construction work at the shop, this felt really good to get back on track and spar with some others in competition. It was nice to be able to run BOTH the 1.3 and 1.7 mile courses concurrently at 2 separate events, and the test data we got was invaluable.



    SCCA Club Trials in the Texas Region is big and growing - they are in year 3 of a 5 year growth plan - and currently they have the largest SCCA Club Trials group in the country. Brad Flak and his daughter Allison ran this event and they did a great job. This region's Club Racing program needs help but they got some new leadership this year, who talked at the drivers meeting.



    On the last session of the 1.3 that day I smoked the right front wheel bearing. It was evident from a pretty loud squeal in the car, and when it happened I came in. It was late in the day and super hot by that point, and I wasn't going to find any time with the elevated track and ambient temps. This failed bearing is the same corner where we replaced a bent control arm when we bought this well used car 2 years ago, so we're going to call this a "deferred maintenance" issue. This day alone the car had 6 full 30 minute sessions on 315mm tires, and we have run this car on track dozens of sessions since we bought it 2 years ago, so this $80 maintenance item isn't unexpected.



    Turns out my 1:10.0 time on the 1.3 mile course was good enough to win the 6 car "Street Prepared" class, and it didn't take a goofy "PAX factor" handicapped time to pull it off. I was bummed we didn't record any data on the 1.3 mile course, so I didn't bother putting any of the video together (this post is long enough!). We got plenty of data that day on the 1.7 - the course we do all of our testing on. See the comparison and progression of lap time drops on the 1.7 course in the next session. We may or may not get some new coilovers with firmer springs on this car before the V8 swap happens, and if we do we'll run it on the 1.7 again, but we will see if that pans out.

    LAP TIME COMPARISON

    Just wanted to point out the various stages and lap times of our FR-S to date

    So in 4 rounds of mods and 6 dedicated track tests we have dropped 5.922 seconds on this 90 second road course.

    Here are a few other laps I have driven in other cars on this same track, for reference. Each of these has a linked video of the lap in question with data:
    By comparison, with almost the exact modifications (Whiteline coilovers and bars, camber plates, and 11" wide wheels with 305mm 200 treadwear tires) and nearly the same amount of tire width increase, our 2018 Mustang GT dropped 9.679 seconds from stock. This was mainly because the tiny OEM 235mm tires on our base model Mustang GT were so woefully inadequate for the power (nearly 480 hp) and weight (3600 pounds) of this car compared to the 2600 pound 200 hp FR-S starting on 215mm tires.

    WHAT'S NEXT?

    Knowing what I do now I would NOT recommend the cheap flares we bought. Just so that is clear - I don't want people to read this as an endorsement of sub-$300 flares vs real Rocket Bunny or Speedhunters parts. We will pay more in the long run (in our fab time + bodywork) to make these fit better, and they will never look as good "as the real thing". But all of these RB style flares need a little aerodynamic improvement, which we know how to do...



    We just wrapped up a customer's E92 M3 track weapon that had some worthwhile aero mods. Some of these might be appropriate for our 86 chassis, some not so much. The "tire walls" on the car above might end up on our FR-S. These keep the leading edge of a spinning tire out of the air stream, which reduces drag considerably. This is something the Rocket Bunny flares do a poor job of, which is what we can fix with some spats (the 5th gen Z/28 and C7 Z06 use "tire spats" from the factory). The splitter on that car is a bit much for what we have in mind for our FR-S, but a shorter version might not be a bad idea to go with an Optima legal 8" chord rear wing we have planned. #AeroReallyWorks



    All of the aero work planned will happen after the V8 is installed, and after we do a track test with these the V8 on 315s. Just telegraphing some things we have in our long term plans for #Agent86.



    Even though we will make the long tube headers using a mock-up block and the T56 Magnum XL trans we have on hand, the actual V8 we are going to use for our 86 is being built soon. We've seen a number of these 468" / 7.7L engines built by Horsepower-Research in use on road course cars. One of these in an Optima competitor's street car makes 660 whp on motor on E85, and we are wrapping up customer's car with another 468" that should make that much or more (using our first set of custom 1-7/8" primary long tube headers). We are shooting for a more modest 550-600 whp range on 93 octane - with better street manners. Will share more of that as the swap progresses.



    We just completed our first production 1-7/8" primary long tube header for a Right Hand Drive BMW E36 LS swap, based off of prototypes we built (our second 1-7/8" custom set built in the last year). The RHD E36 LS swap parts and headers should be shipping in a few weeks, then we will begin making new headers for our 86 swap by that time. Finally.

    More soon,

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above



    We came back and Evan added the Rivnuts - a threaded insert that goes into the sheet metal with a special rivet installation gun. Then a bunch of stainless M5 button head Allen bolts attach the eight fender flare parts to the body, for a semi permanent finish that can easily be removed (unlike rivets). Oh and we used different "expanding" style rivnuts on the plastic bumper cover portions vs the style used on the sheet metal.



    So that was the install. MyShopAssist shows we spent 27 hours over the course of 8 days doing this work, and there's still a few hours of final welding needed out back and to put in some blanking plates for the front lower frame horns (still open for now). Yea, that is a lot of work, and this was the first time Evan had done flares here at Vorshlag using all of the steps I require. Might be able to trim out 3-4 hours on the second one he does, but that's just what it takes to do it right: to check for proper tire clearance in bump, to get full lock steering clearance, and to modify parts that don't fit like they are supposed to. On a normal flare job that doesn't require this much front frame/fender cutting, we tend to take closer to 17-20 hours.



    There were at least 2-3 hours spent fine tuning the fit of the poorly made right side pieces in that total. These later pictures from our MSR track test (above) show how that side fits now. Evan added some bolts & nuts between the two rear parts to line them up better, then trimmed the trailing edge of the front bumper section on the right front to get it to look right. Again, starting with a costlier, higher quality flare kit up should save some time during install and painting.

    CUSTOM RAM PHONE HOLDER + VIDCAM MOUNT

    Having a sturdy, easy to use phone holder is very important to me. I invest a lot in my smart phone and I live and die by this thing - it reminds me when to wake up, has my "to do" list and calendar, email, Facebook, navigation, potatocam, and streaming music stations. Our phones go with us everywhere, and with a great navigation system they need to be visible when we drive. A year ago we built a custom phone holder for my daily driver work truck and its been the most functional add-ons we have made.



    Unlike the choice behind the 1/10th cost knock-off flares above, I normally preach that You get what you pay for. And again I learned that if you spend a little more up front to get quality, you will be rewarded in the long run. These U.S.-built RAM mount components fit that theory nicely.



    For several previous vehicles I have purchased and tested a number of cheap Chinese phone holders. After using each of these for a few days I realized that they are garbage. GARBAGE. The dash mounted unit I had in my old shop truck (#TruckNorris, see above right) was somewhat flimsy, didn't hold the phone securely, and snapped in half during a rear end collision - sending my $900 smart phone flying into the windshield at 60 mph.



    I have always used RAM mounts for lap timer/data loggers and windshield suction cup camera mounts. They are rugged, easy to adjust, use a standardized 1" ball for mounting at either ends, and standardized bolt hole spacing for an array of "device holders" and suction cup ends. When something is important in a race car, I use a RAM mount - so why not for a costly smart phone or vidcam in our 86?



    I asked Evan to build a similar setup to Amy's FR-S, which helps with street driving and track use. Once again I purchased a number RAM modular mounting parts including a RAM (RAM-HOL-PD3U) Universal Spring Loaded "Large" Cell Phone Cradle Holder, RAM "Diamond Base" with 1" Ball to mount to the phone holder, and a Composite Double Socket Arm for 1-Inch Ball Bases. Initially I was hoping to use another (RAM-B-202U) Round Marine Electronic 1-Inch Ball Mount Base to bolt it all to a flat portion of the dash.



    We were hoping to mount it behind the dash trim then just drill a hole in this trim piece and have the 1" ball slide through, but once Evan pulled the plastic radio dash trim surround (top left) out of the way we realized there was no surface flat or big enough behind there to mount to. There was a few bits of plastic and an air gap. Hmm.



    Instead I ordered the RAM 1/4-Inch-20 Female Threaded 1-Inch Ball (RAM-B-337U) and then Evan just drilled a hole in the radio surround trim panel, then bolted that ball mount in place. It isn't quite as rigid as the 4 bolt marine plate, but it works plenty well. We might tweak this a bit after some more street testing - the plastic dash trim wants to flex a bit when you really crank on the phone holder.



    This arrangement of parts in the FR-S is nearly identical to the phone holder setup in my truck (above). The one issue we ran into for both vehicles was - the biggest RAM phone holder isn't quite big enough for the large frame of my or Amy's "Plus" sized iPhones with a case. To fix this we cut off the two "fixed" plastic claw mounts and add a custom made section of formed aluminum sheet in its place. This was cut, bent, then riveted to the end of the RAM holder, extending the clamp's reach by half an inch. This worked perfectly to fit our Plus sized phones with cases. The bottom "claw" section can still clear a charging cord, too.

    I've been using this same RAM phone holder setup for over a year in my truck and absolutely love it - others have seen and copied it. I can install a phone into the spring loaded RAM holder with one hand, blindfolded. Installing it just takes a bit of downward pressure on the moving jaws, then it pops into the upper and upper jaws of the holder. The 4 adjustable side pins keep the phone aligned laterally and the upper and lower jaws hold it in the other two axis. It won't move a fraction of an inch within the holder, and the RAM arm and base keep the holder from moving relative to the vehicle. Should survive a crash, too.



    Since the RAM mounts are modular, and the placement was high enough on the dash of the FR-S, I was able to swap out the RAM phone holder portion for my video camera mount (the same RAM marine 4-bolt base with a section of 1/4-20 threaded stud) in seconds at the track.



    This makes mounting our Sony video camera for track use that much better. I no longer have to run a suction cup mount on the windshield and position the vidcam upside-down, so I don't need to "flip" the video before I merge with AiM data. Woo! Overall this was a relatively simple upgrade that makes the 86 that much more street friendly - with some additional use at the track.

    TRACK TEST #6 - MSR-C 1.7 CCW & SCCA CLUB TRIALS MSR-C 1.3 - Aug 25, 2018



    After a 3.5 month hiatus from doing any track events, we were finally back at the track once again - for a double header! First, we came to test the new tires and make sure there was no tire rub before final welding the rear unibody and front frame horn.

    Event Gallery of photos: https://vorshlag.smugmug.com/Racing-...-MSR-C-082518/

    In the morning I did a session on the 1.7 CCW course (member day) to test times vs previous best in this car. Amy also ran two full sessions on the MSR 1.7 that day. Secondly, I ran 3 sessions on the separate MSR 1.3 course, competing with SCCA Club Trials for some head-to-head comparisons on the new tires. Long hot day but we got a lot of seat time, lots of test data on the car, and had a blast while doing it.



    We unloaded the FR-S and had it fueled up and loaded with data logging and video camera equipment by 7 am. The durometer on these used Rival-S tires was tested at "60", which isn't far off the mark for a fresh set of Rival-S tires. I set the cold pressures at 28 psi then got all of my track gear on. Still no race seats or harnesses in this FR-S, but the stock seats are "less terrible" than the base seats in my '18 Mustang.

    TRACK TEST #6 ON MSR-C 1.7 CCW



    I was on track by 7:30 am on the 1.7 CCW course, running behind our customer/tester Jerry Cecco in his C6 Z06 at this "member day" event. The ambient temps were good for this whole 30 minute session - only 74deg F - which is damn near perfect for late August in Texas! It only took a couple of laps to get these giant 315mm tires up to temp and they were pulling some big grip numbers. Jerry and I had the track to ourselves for the first ten minutes. An overcast sky kept the ambient temps low for this session, but it crept up to 98°F that afternoon, which is more normal for this time of year.



    First impression: the FR-S was much much easier to drive with the big tires. Lateral grip for days, with data showing as high as 1.38 g in some corners! Compared to the previous 215mm tire tests here, with the 315mm tires I never lifted from full throttle for T1 (Wagon Wheel), T2 (Ricochet), or anywhere in the 3 lefts after T5. I barely touched the brakes into T8 (Big Bend) as well. After watching this video I feel like I was under driving it into a few turns, but it was such a big change in lateral grip from before it was hard to tell where the limits were.



    The video above is from the "second" half of this 30 minute session, where I had working video and audio. It showed a big drop in lap time from the tire switch, the most we have dropped with any single mod, a whopping 2.6 seconds quicker! Once again proving that you can NEVER have "too much tire", even in a 2600 pound car with only 200 hp. Did I get enough heat in these tires? Of course - within 2 laps they were making max grip, and after 7 laps I was overheating the rears (to the point that they got greasy).

    In the first 9 laps of this session I managed a best time of 1:26.005. I came into the paddock because the remote mic had fallen on the floor, so we removed that, made a tire pressure adjustment, and I went back out in the same session and ran another 5 laps. I managed a nearly identical 1:25.978 lap on video that time. In that second half we had some additional traffic that had joined us - you can see the screaming fast GT3 cup car and a Corvette I let go by in my video. I did get to pass both a McLaren 670S and GT3-RS, which was pretty hilarious!


    GT3 cup Race car (left) and Jerry's C6 Z06 on fat Hoosiers (right) were some of the 5-6 other cars on track

    Mods have been well documented here, but include: Whiteline Max-G coilovers, 400#/in springs, Vorshlag camber plates and shock mounts, Whiteline bars at both ends, Powerbrake 330mm 4 piston brake kit, 100% stock drivetrain, and now these 315/30/18 Rival-S tires (used) on 18x11" Forgestars.



    As for settings - the shocks feel great with these somewhat soft spring rates (400#/in front and rear) and didn't need a lot of massaging. Tire pressures did: I went out at 26 psi cold but when I came in the pits in the middle of this session to check tire pressures, Amy bled them down 2 psi (from 32 psi to to run at 30 psi hot). This comes down to 24 psi front and rear, when the tires are dead cold.



    As you can see above the camber loss in these higher g corners is significant. We ran the same -3.5? front and -2.2? rear camber static settings but with this much grip it looks like now we need a bit more. And sure, a full IR temp array would tell us this more accurately, but we can still see a lot in these close-up, loaded corner pictures and long term tire wear. At full loading, both outboard front and rear tires show about zero camber (radials like to still see a little negative, loaded). The C6 Z06 ahead shows positive camber loaded - and his 335/345 Hoosier R7 tires are wearing out faster on the outer shoulders. We will dial in a little more camber into #Agent86 next time.

    continued below
    Last edited by Fair!; 05-15-2022, 01:11 PM.

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above

    MEASURING FLARES ON AN 86

    We got a bit of a preview for the flares on an 86 chassis earlier in 2018, and we spent some extra time on our own to see what would fit on the off chance we went with these flares on #Agent86.



    This car was purchased by a guy in the service, and dropped off by his dad at our shop in March of 2018. It was purchased like this and his dad noticed tire rub at full lock, so he brought it in for us to clean up some of the bodywork to clear these high offset wheels and tires. This car had one of the Rocket Bunny style flare kits (Rocket Bunny or Speedhunters), which we fixed. Then measured for even wider tires... and it gave us the ideas for what we might like to do to our red car. We couldn't tell which brand of flare this was, so that is still a bit of a mystery.



    This car had 18x9" fronts with 265/35/18 tires (which we can fit under stock fenders), but as you can see below it had inches of clearance inboard to the struts. We had to clearance the front frame horns behind the front tires to clear the high offset wheels at full lock. The wheels had been pushed out as far as possible to make the front track wider, and they used a super low offset Forgestar F14 Super Deep wheel.



    Out back it was at least a little wider than what you could fit under stock fenders. It had 18x11" rear wheels with 295/30/18 tires, which were stretched a bit. Again built with offsets to really push the tire outboard - almost poking. But once again with several inches of room inboard we knew with confidence we could fit an 18x11" wheel and 315/30/18 tire - or even a 335mm tire on a 12" wheel, with room to spare.

    AND THE FLARE KIT CHOICE IS..?

    Were there issues with these flares that were on this car? Sure, but ones we felt we could overcome. Just seeing an 86 with this style of flare was enlightening - it showed just how much more tire we could fit with the right offsets, camber, etc.



    We knew we could at least fit 315mm tires under this flare kit, which could be a good starting point for dealing with V8 power. And experience said the 315s still wouldn't slow down the car with even FA20 power, and should actually drop a chunk of lap time. Yes, even though the internets say they will "never get up to temp" and that it would add "tremendous rolling resistance"



    Ideally it would have been nice to do something custom, or use a full carbon widebody like the race car above, but we have to be realistic. We ultimately want a street car that has AC and is street legal and is fast on a road course and autocross. I would rather be cautious with the flare choice up front, test it on track before and after V8 power with a 315mm tire, before locking ourselves into some expensive and elaborate body kit or dozens of fab hours on a custom built version.



    How bad could the lower cost version of these flares from Extreme Dimensions be? If we could get the car to look this good, and fit at least 315mm tires, for under $300? I figured that was the best bet and ordered the Extreme Dimensions "Duraflex" kit (a flexible fiberglass composite). This company makes TONS of parts for the 86 chassis - multiple flare kits, carbon hoods and trunks, front and rear bumper covers, spoilers and more. We have had some success with this brand before, so I pulled the trigger on these two part numbers below.



    This was the front flare kit above, which has 4 pieces to complete the front fender flares.



    And here is the rear kit, also 4 pieces, which completes the rear fenders. The other options were $3000+ with shipping, and these Duraflex flares were under $300 shipped. 1/10th the cost... let's see how they fit!

    INSTALLING LOW COST FLARES

    We unboxed the flares and they looked fine, so now it was time to mock them up on the car. Loads of 3M painters tape was applied to the body and these flares were taped in place.



    What we immediately noticed was that there would have to be some significant cutting on the fenders to even get these mocked up. The rear of the front wheel arches has to be cut away before these will lay flat, for instance. But for the most part they looked like an OK fit. It would take cutting and Cleco mounting to know more. Let's cut!



    The fender liners were all pulled out and then the front fender arches were trimmed. The rear of the front wheel arches had to be cut out. Now we could drill the mounting holes for the flares and snap in some Clecos...



    The main flare on this first mock-up didn't line up so well with the the front portion that mounts onto the front bumper cover. We needed to trim some more metal and slide the flare rearward before this would fit. It was also time to cut off the fender to improve the fit.



    Another area that needed serious trimming was the front end of the rocker. We learned this on the white BRZ that came in back in March, but with 315mm tires swinging to full lock on an 18x11" wheel, we needed to trim our FR-S even more than that car.



    Another part that needs to be modified for this 25.5" tall 315/30/18 tire to clear at bump travel is a vertical flange that is part of a pinch weld on the front upper frame horn. This is the curved, welded, tubular section that runs above the tire, upon which the front fender bolts to. The bottom section has a ~3/4" tall flange that Evan hammered flat, shown above. This way if the tire goes up in "bump" travel too far it will rub against a flat section of frame instead of a sharp vertical flange.



    Evan tested the tire at full lock, full droop, and at ride height many times before finalizing the clearance work on the left front. Then he transferred the same cut marks to the right front and cut that, too.



    This is the final front fender flare mock-up, and I was happier with the alignment. At least on the left front the two pieces almost lined up, and with some tweaks by our painter Shiloh they would look even better.



    On the right front the two pieces refused to cooperate, and the alignment was pretty poor. The main flare section fit like it should but it was the front bumper cover part that mates up so poorly. We adjusted this later, which I will show below, but it's going to need some real fiberglass work to get these pieces to line up "right". This is one of those compromises that comes with starting with the 1/10th cost version of the flares.



    The rear flares and trailing sections were mocked up next, and once again the left side fit together much better than the right. The "add-on" piece on the right side didn't line up at all but we felt that our painter could make it all fit better - at a cost. So once again, saving on the flare kit up front will cost us more on the back end with the bodywork.



    The left side fit so well, too. This is how these multi-piece flares should line up. The right rear pieces had 3/4" of mis-match, ugh. At this point you could see how much more room we had out back - could easily fit a 335mm wide tire. Oh well, this set of 18x11's has the same offset on all 4 so they are rotate-able. A staggered 18x11" front / 18x12" rear would not be (it would be hard to fit 335s up front without massive surgery!)



    The back of any unibody built car is the MOST work when clearancing properly for big tires under flares. Big sections of the rear fender have to be cut off and this can be 2 or 3 layers thick back here. Once you cut off the outer skin the inner wheelhouse sections are then "pie cut" (above left) and these curved sections are then metalworked and bent upwards, to intersect with the outer skin of the new wheel arch.



    These sections usually curve and form a sort of a bowl around the skinny stock tire - but to fit 4" more tire width per corner we have to make room above the tire for "bump" travel. After working them, the sections are now horizontal and the opening itself is moved upwards about 4" from the stock contours. The overlapping pie cut pieces are tack welded to the outer skin and then we are ready to test.



    This part is a NASTY job - because the primer and paint has to be removed from both the inner panel and outer skin, and even then they don't weld together very cleanly. We move to a MIG welder for this work, and it often catches the undercoating on FIRE. So the interior in the rear of the car has to be removed during this step, and a second tech with a spray bottle of water is nearby to put out the undercoating flare-ups. THIS IS A JOB FOR A FABRICATOR.



    So what looked like we needed "just a little bit of clearance" out back has turned into a chasm of room. As the fender is cut "upwards" it also contours "inboard" and the resulting clearanced rear fender looks a LOT different when completed. This is the exact same wheel and tire, no tricks - that's just what happens on most rear fenders when you cut for proper bump travel. Don't worry, the flare covers ALL of this area.



    Again, this is what is necessary for proper tire clearance with real suspension travel. This is what the showcars rarely ever do properly - they WANT tire rub, it is some sort of badge of honor to them. Well racers don't look forward to cutting tires, and now we have FOUR INCHES of vertical bump travel clearance for the rear. Which is more than enough for this ride height and coilover.


    Out in the sun for a test drive - showing the "good side".

    The rear fenders were Cleco'd in place and I took the FR-S out for the first test drive, with Evan riding shotgun listening for tire rub. We noticed a bit of rub at full lock up front, but it was tire rubbing on frame on the front side, which cannot be fixed. This is normal on a giant tire like this and something we can live with. Nothing else touched, but we did lose a Cleco along the short one mile drive.

    continued below
    Last edited by Fair!; 09-25-2018, 09:09 PM.

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    Project update for September 10th, 2018: Last time I said we had stopped driving the FR-S and would be jumping into the V8 swap. We had a bit of a detour and made one more little change to #Agent86.


    BEFORE (left) and AFTER (right) - as you can see we have added flares, 18x11" wheels, and +100mm more tire per corner

    We changed the tires, wheels, and added some flares. A pretty significant change, but one that I wanted to test before we tore the car apart for several months. It was hugely gratifying and once again proved out "you can never have too much tire" theory, which we apply to everything - even 200 hp 2600 pound cars.


    We believe data more than hearsay around here... so lets test this theory at the track

    Will the big tires "never get up to temp!" and have "so much rolling resistance!" (predictions we heard before this test) that the car will slow down on the MSR 1.7 CCW road course? Or will it pick up some time - a little, or a lot? We have argued with interweb experts for 30 years preaching the "narrow tire" theory, but with little or no data to back up their conjecture. Do you believe everything you hear 3rd hand on the internet, or do you believe MEASURED DATA that is shared openly? I say we let the clocks tell us what is what, at a another track test - our 6th dedicated track test in this car on the same course with the same driver.



    This post also shows the steps required to do a proper fiberglass flare install for BIG tires, then we go over various quality levels for these 86 flare kits (you can learn from our "low cost flare kit" mistakes, too!) We added a somewhat small mod that might help with your daily driver and also has some function for track use (a RAM modular video camera + phone mount). And we show our first part that has failed from track use on this car - and explain how to fix it. Read on to learn more.

    MAJOR MOD: ADD GIANT 18X11 WHEELS + 315mm TIRES!

    In my last update I had summarized all of the MSR-C 1.7 mile CCW lap time drops we have seen in our red '13 FR-S (#Agent86) over the past 2 years of tinkering. After 5 dedicated track tests to get that "magic lap" but we have shown a 3.34 second lap time drop (1:31.90 - 1:28.56) on a 90 second road course - all while using the same cheap 215mm tires, stock aero, and an untouched drivetrain.


    Nothing but the best for our test car! LOL

    Then I mentioned that "A bump to better 255mm street tires" would drop at least 2 more seconds, if not more. As you can see above pics of right after this last track test, these 215mm Firestones had seen better days. We got our money's worth! The durometer numbers were still ok but they were getting down to the base rubber. This set of 17x7" wheels were pretty banged up when we got the car, with one bent wheel (on the same front corner that had the bent lower control arm when we bought it, that we replaced). I regret never having upgraded to an "interim" set of 17x9" wheels and better 255mm street tires, but I hate buying things twice.


    Many things have kept us busy from February-August 2018 - new shop construction, shop move, and a new project car

    I had hoped we could jump right into the LS swap after that last track test. Well we got really busy in the shop, and I got buried with construction of our new "bat cave" shop (not open to the public) from May-August, the shop move in June, setting up existing and adding some new CNC equipment (June-August). To make matters worse I purchased 2018 Mustang GT (they gained a good bit of power with a DI engine that year) and added a hectic development and track test schedule (Feb-May) for that as well. Side note: we added the same "Whiteline" coilovers to this 2018 GT, which also had the somewhat soft rates (400#/in fronts), but they worked well enough and we dropped a staggering 10 seconds on our MSR road course test, from stock to round 1 of mods. (Note: the Whiteline/AST private label shock deal has since ended and we have removed all of the "Max-G" coilovers from our website)


    This 17x9" wheel and 255/40/17 BFG Rival tire package is one we tested back in 2013 on Vorshlag Matt's BRZ

    It always bugged me that we would be jumping into the V8 swap before putting "real" wheels and tires on the car. Now I was wondering if we should step back and buy the 17x9" Enkei and 255mm Rival-S or Bridgestone tire so many STX autocrossers use on these 86s. But with 500+ whp those would still be scary. If we tried a track test on these 2 year old, bald, 215mm street tires would it be a TOTAL mess with triple the stock power.



    So we decided to test for a "max fitment and beyond" wheel and tire fitment. We brought the FR-S into our Plano shop right before our planned shop move and checked inboard wheel room from the itty-bity 17x7" stock wheels. The pictures above show the stock 7" wide wheels' proximity to the struts and shocks inboard. LOTS of room. Plus there is room outboard.



    We also mocked up a 315/30/18 Rival-S tire we had onto the car using our wheel checking tool, shown above. I didn't get a picture of this step but the image from the same tool used on a 335/30/18 on the wide body M3 V8 above shows what it looks like.



    The tender spring + main coilover spring stack up high enough on this AST coilover to gobble up some inboard room, but even fixing that issue (we have tricks) there was still no hope of fitting the 11" wide wheels under stock fenders. Sure, we could have fit a 9.5" front and maybe 10.5" rear wheel under rolled fenders if we really needed to, but we wanted MOAR! We decided to use a Rocket Bunny style flare kit, so inboard room wasn't a huge concern.



    So we tried something bold - I decided to jump ahead to the giant wheel/tire package we had always planned to use with the V8 for Optima series competition. We ordered these 18x11" Forgestar F14 Super Deep wheels shown above.


    This set of Rival-S tires was new in Feb 2016 - and they were used for several weekends on this car

    I bought a set of lightly used, but still fresh at 60 durometer 315/30/18 BFGoodrich Rival-S tires from a customer, Jamie Beck, back in late 2016. He used these for testing before he jumped feet first into NASA ST3 racing where he has been on Hoosiers ever since. This set were still soft enough, so worthwhile for this brief "big tires matter" test.

    Jason and I measured the 86 for an 11" wide wheel at both ends. Why? Well because every car I own needs to have a tire "starting with a 3". I also feel that you can never have too much tire, and with the V8 we will definitely need this width.



    We ordered Forgestar F14 wheels with their "super deep" profile for the first time - this used to only be an option on 19" F14 versions, but now they also offer this in some 18" widths. We selected custom offsets that should work at both ends fairly well, so we can rotate front to back and still not use a spacer. There is a bit of mystery with every new, radically new wheel fitment like this but we were fairly confident this would fit fine with the flares we chose (see more on that below). We weren't trying to squeeze an 11" wheel under stock fenders so they don't have to be like 2-3mm off the strut or other inboard parts to squeeze a max width under there.



    Pro Tip: After the tires were mounted and balanced I taped the stick-on wheel weights in place with aluminum tape (you can find this in hardware stores near the roofing section). You have to clean the wheel surface well but this tape sticks better than the adhesive on the wheel weights. More surface area, too. Why does this matter? Get the wheels hot and watch as your $15/wheel balance job goes to crap as the weights fly off. This happens EVERY time I forget to add this aluminum tape to the weights! Cheap insurance.



    One of the downsides to the unusual 5x100mm bolt circle used on the 86 chassis is that the lug holes have to be smaller than normal, so our 17mm hex open ended lug nuts will not fit. That isn't the case on the many 5x120/5x114.3 wheels we normally get from Forgestar. The larger lug wells encroach into the meat of the wheel hub area so we had to choose splined "tuner lugs", which have a smaller diameter and use an adapter socket to engage the splined outer diameter of these lug nuts.



    Once we had the tuner lug nut set on hand we could finally mount up the new wheels, set it on the ground, and take a look. As you can see we only need about 1.5" flare up front and 2" flare out back to clear these at a lowered ride height. Nobody makes a flare that small, of course, as the #StanceBois want the MEGA flares and silly offsets that push the wheels way outboard. The opposite of what we shoot for...



    Overall I was happy with the way these Super Deep F14s looked on the car, but worried they might be too inboard in the rear for the flares we had chosen. I measured the outer track width (to the outer sections of the tread) and noted we had gained a good bit of outside track width from stock!



    Above shows this measurement in stock form (left) and now with the 18x11s (right). The 68-1/2" pic it was our very first picture in this forum thread, way back from August 2012. The reason that was the first pic 6 years ago was because that 68-1/2" outer track width was a freakishly wide for a 2600 pound RWD car. And the wide track width is partly why the 86 chassis makes so much lateral grip for its weight and tires installed - adding track width adds lateral grip, directly.


    This BRZ on 17x9" wheels had 2" more wheel width per side than stock - and logged 1.25g lateral on street tires!

    For reference, I just measured some outer track widths on a sampling of cars in our shop: 63" was an NB Miata track car on 9" wide wheels; 65" wide for an E36 M3 with 8.5" wheels and 245mm tires; 68" wide on a tube framed 69 Camaro with 345mm Hoosiers; and 76" wide on my 3600 pound 2018 Mustang GT is on 19x11" wheels with 305mm tires. This 2600 pound FR-S is now 74" wide with the 18x11s!


    ...this is NOT how to add big wheels to an 86! #StanceFail

    We did NOT add all of this added wheel width outboard to exaggerate the track width, like the meme above shows. The 68-1/2" OEM width was with 215mm tires and 7" wide wheels. We added 100mm of tire and 4" of wheel width per corner but only gained 5-1/2" of total outer track width. If we went purely outboard on the addition it would have gained 8" of track. The typical showcars we see mount up 9" or 10" wide wheels on these cars and do just that - add it all outboard, and then some.

    GOOD QUALITY VS REALLY CHEAP FLARES



    After much searching I found 3 sources for essentially the same Rocket Bunny style flare kit for the 86 chassis, listed from most expensive to least: Kei Miura designed Rocket Bunny / Pandem aero kit (3 variants, including one shown above), the Speedhunters KM4SH body kit (shown below), and the Extreme Dimensions flare kit we purchased (see below).


    This white car (for sure) has the KM4SH flares from Speedhunters

    As much as I wanted to get one of the kits from the first two suppliers, this was all a huge gamble and their prices were pretty high ($2000-4000) for what might just be an experiment. I had previously settled on the Speedhunters kit (priced at $890) but when the shipping came out to $1300 it pushed it into the "too risky" zone for something we were not sure would work for our project.


    The Genuine "Rocket Bunny" version 1 or 2 flare kit shown on Forgestar's website with the Super Deep F14s

    Honestly, I'm personally not a huge fan of the Rocket Bunny style flares. We weren't sure that whatever quality level of Rocket Bunny kit we purchased would stick around on our car. The aerodynamics of these kits is OK in some aspects but poor in others. Most of the showcars that use these set their ride heights so low and offsets so #HellaPoked that they aren't even functional (tires touching). We looked at a bunch of these RocketBunny equipped 86 cars at SEMA2014 and just were not all that impressed with the tire fitments anyone had. Some had 245mm front tires and at most 275mm rears. We knew we could fit that and more under stock bodywork - but what could you really fit under these kits?

    continued below
    Last edited by Fair!; 05-15-2022, 01:03 PM.

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above


    This is a track map of the 1.7mi CCW course for NASA TT - ignore the "bunch up" and "go green" lines

    I started looking for more 1.7 mi CCW dates at MSR Cresson and hoped to jump into a member day instead of a busy HPDE event again. It is so much easier to extract everything a car has when you have 1-5 people on track rather than 15-20 - I was on the hunt for clear traffic. And warmer weather.

    TRACK TEST # 4 - MSR-C MEMBER DAY, FEB 3, 2018

    Gallery: https://vorshlag.smugmug.com/Racing-...k-Test-020318/



    On Saturday Feb 3rd a couple of friends (Jerry and Kevin) that have MSR memberships were going out, the weather forecast looked a lot better, so I joined them once again in our FR-S for track test # 4.



    The weatherman missed it by 24 hours - Saturday was still pretty freagin' cold and Sunday the 60°F weather finally hit. Of course we had planned on Saturday. It ended up being slightly warmer than two weeks earlier in January, and the lap times dropped a fraction. We waited until about 10 am to go out, to let the track warm up a bit. Still had heavy winds which made the wind chill still near freezing.



    I went out in my first session at 10:30 am and it was 50°F, but with wind chill still in the 30s. I ran 11 laps in the FR-S in that session but all I could muster was a couple of 1:29.5 laps and a bunch of laps slower than that. There was more traffic than I was used to seeing on a member day, and I was sliding around a bit on cold tires.


    I came in after this first session and saw that Jerry's Z06 had thrown the serpentine belt

    Between sessions I checked tire pressures and also the condition of the tread. There were the same big chunks missing from the outer tread blocks of some tires, all from our very first track test. I kinda chunked the tires back then, but we keep rotating and flipping the tires to hide that. I went out again after lunch at 1 pm and the ambient temps had warmed up to 53°F. Not ideal, but still better than earlier, and better than January.



    For reference here are two Corvettes loaded up in the fastest turn, Big Bend. The red C7 Z06 is stock but on Michelin racing slicks. The black C6 Z06 is on 335F/345R Hoosier R7s. They both have a good bit of bodyroll. Both guys were a couple of seconds off their best ever laps on this course.



    Here is our FR-S in Big Bend the same day, same session. In that session I ran the best lap ever in this car (1:28.56), but it wasn't exactly an earth shattering time. The g loading data did tell us something: I hit .92 g under braking several times and 1.17g and 1.16g laterally (right and left) on several corners of my best lap. Funny how that works - we put on better dampers, stiffer springs and swaybars to reduce roll, and the grip levels went up, lap times went down. Yet in the images it looks like it has more roll than test # 3. Since the times were faster, and g loadings were higher, the added roll makes sense.

    The video below shows parts of three laps during this 9 lap session. Something happened to one of the GPS start/finish line trips on the first 2 laps and my AiM lap counter got off by a bit - so add 4 laps to each lap shown on the counter embedded in the video below.


    In-car video of our best laps of the day

    If you watch this video you will notice that on lap "2" (really lap 6) I had an "Ice Mode" ABS situation (brake temps got hot and "stopped stopping") into Turn 10, after braking super late into Turn 9. Some who have seen the video have asked "How is that even possible with Powerbrake fronts?" Two reasons: First the rear pads we installed when we put the car "back to stock" were $22 worth of cheap O'Reily house brand pads. Second we have ZERO brake cooling on the fronts - and I was abusing the CRAP out of the brakes for 6 "qualifying" laps in a row to try to find that elusive "1 second improvement" from Test # 2. I found it, but it took some crazy driving to get there. After a cool down lap I did another few hot laps and found the time.


    Braking into turn 9 on track test # 4

    From looking at images from Test # 2 and #3 (both with Powerbrake BBK fronts) I never saw the front end diving like this under braking into Turn 9, but it was this time! I was loading up the brakes pretty hard and we will address this by adding some brake cooling ducts before our next track outing. Overall I was happy that we could eek out more grip and found another second from Test # 2 this time, but I know that the 14 month older tires weren't helping things.

    WHAT'S NEXT?

    It took two more track test outings to get that "magic lap" but we did it, and now have shown a 3.34 second lap time drop (1:31.90 - 1:28.56) on a 90 second course - all while using the same cheap 215mm tires, stock aero, and an untouched drivetrain. A bump to better 255mm street tires would drop at least 2 more seconds, if not more. The car still drives great on the street, bringing no compromises, and Amy usually daily drives it to work.


    This was what the shop looked like today - with 4 cars moved outside so we could work!

    The daily driving has stopped, and as soon as we can literally fit one more car in the Vorshlag shop (we are at capacity and turning away work for the moment) we will get the FR-S in here and do this...



    Next time you see an update from me our FR-S should look like this - motor out and getting an LS V8 swap. I will have the stock FA20 engine and 6-speed trans for sale at that time.

    More soon,

    Leave a comment:


  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    Project update for February 19th, 2018: A short update this time to cover two recent track tests in our FR-S, track tests #3 and #4. These tests were done to get a representative lap time with the Whiteline coilovers and swaybars on the same 215mm tires.



    The first opportunity we could find to run the 1.7 mile CCW course at MSR-Cresson after our December round of suspension installs was on January 13th with Apex (track test #3). The weather fought us in January so we did a re-test (#4) on February 3rd at a member day - where it was a little warmer.


    Left: Track Test #1, August 27, 2016 (bone stock). Right: Track Test #2, November 10, 2016 (Powerbrake BBK + camber)

    As a refresher the previous two track test in-car videos are linked above. Track test #1 yielded a 1:31.90 time, which became our bone stock baseline lap. Test # 2 was done after we added the Powerbrake front brakes and camber plates, and a 1:29.630 lap was thrown down. All previous track testing as well as these two recent tests were on the little stock 17x7" wheels, 320 treadwear 215mm Firestones, and stock power. These tires are not that great but similar to the stock rubber these cars come with, and have been somewhat consistent. Ideally we would run the same tires at each test with the same number of heat cycles, but the reality is the tires were much fresher in the first 2 tests in 2016 than the last 2 in 2018.



    In a perfect world we would have brought another set of upgraded wheels and tires to run at these same tests - the little 215s are REALLY holding us back at this point. We tried to beg/borrow/rent a set but it didn't work out. I almost bought a used set of 17x7" wheels and 215mm RE71R tires, but it was just too much $ for such a skinny set that would be used for ONE track day. Our next round of mods has a massive upgrade in wheel width and tire compound planned, where we hope to add +100mm of tire at each corner.

    TRACK TEST # 3 - APEX HPDE AT MSR-C, JAN 13, 2018

    Photo gallery: https://vorshlag.smugmug.com/Racing-...W-Jan-13-2018/

    When we finished the latest round of suspension updates on our shop FR-S on Dec 18th we searched for the next date at Motorsport Ranch Cresson to find a member day or HPDE event held on the 1.7 mile CCW course. With Christmas and New Years thrown in there plus some cold weather the first date to open up was Jan 13th.



    This was an HPDE event held by the Apex Driving Academy, one of many Dallas area groups that runs at this and other tracks in Texas. Apex is unique in that it only runs at MSR and it always does 1 day events - unlike the 2 day events many groups do. This makes it easy to drive out, drive 6+ sessions a day, and head home. No hotel or 2 day commitment needed, which is perfect for what I wanted to do - just run a few sessions in the FR-S, to find a good lap time.

    Gallery: https://vorshlag.smugmug.com/Racing-...W-Jan-13-2018/

    I signed up for this event about a week in advance, when the weather forecast looked great. The 13th was a Saturday, which was also my birthday. Can't think of a better way to spend that than at the track, and Amy joined me for trackside support. We got there early and checked in only to find that most of the people running this event were NASA, SCCA or BMWCCA racers we already knew well, and a bunch of our customers were in attendance as well.



    This group limits entries to under 75 but gives drivers 6 sessions on track, for a busy day with lots of track time. They put me in the Advanced group, where I hoped that our 200 hp car on crappy tires would be able to stay out of the way yet get some traffic free laps.

    Well the conditions didn't work out for us that day. The temps were VERY cold for Texas, even for January. Ambient temp was 24°F and very windy when I went out on track in session 1, so it was like driving on ice. The traffic was pretty thick and everyone was slipping and sliding around. I got some heat in the tires and was passing a lot of cars that I thought should be faster and I put in 9 laps with traffic, with grip levels were around 1.00 g sustained. Best lap of 1:30.673 was way below what I knew the car should do.



    I also ran out of fuel in the closing minutes of this session. There were so many dash lights on I didn't notice the low fuel level and ran smooth out, stalling on the edge of the track out of the way of the driving line (the grass was so dry they asked us to NOT pull off track if possible, to avoid grass fires). Of course this ended the session about a minute early and I had a flat tow into the paddock, head hung in shame. Over 30 years of track events and I had never run out of gas before - I guess it was bound to happen. Splashed 5 gallons of 93 octane in the tank, then drove to the gas pumps to get about 3/4 total fuel level.

    I skipped session 2 because ambient was still below freezing, then went out after it warmed up to "balmy" 48°F, but it was still bitterly cold due to the wind. I got 12 laps in this session - all but 2 in traffic - that were finally quicker than track test # 2. Sustained lateral grip levels of 1.05g with spikes to 1.12g on the data logger.


    In-car video from my best laps in session 3

    The session above was frustrating on several counts. First the traffic was pretty thick, and I also had never run on track with a lot of these folks. Many cars I was passing in the first advanced group session when it was 24°F were now faster than our FR-S, and I had to let them by. Lifting to let a car pass ruins your lap, as does passing when the driver ahead doesn't line up and point you by at just the right spot on track.

    Second was the tires - they felt inconsistent and were not coming up to temp or working like I felt they should. 14 months of street driving and hundreds of heat cycles had "compounded out" these tires a good bit. To top it off, I had a migraine headache which was getting worse. By the end of this session I was having trouble seeing, so after 12 laps I came in.



    Looking at the pictures of the car loaded up in the big corners above in test # 3. We could still see a good bit of bodyroll - even with the bigger bars set to full stiff. This is only slightly less than in previous tests but a bump up in tire width and compound will definitely need a bump up in spring rate.



    The image above is from test # 2, with stock springs/bars/shocks + our OEM version camber plates. You can see more roll above with the stock springs/bars/shocks. Still we will try the new Whiteline coilovers with stiffer springs in the future.



    Our Tremec transmission supplier was nice enough to meet us at the track and deliver our T56 Magnum XL to us! This is the 6 speed monster that will be used in this car with our LS V8 swap. We arranged for the guys at G-Speed to bring this by when they came to Vorshlag in a couple of weeks.

    We left by about 2:30 pm as more and more drivers were starting to go out on track in the warmer weather, so traffic would only worsen. And my head was pounding - thankfully Amy drove us home. With less than a second of improvement from test # 3 I vowed to come back for a retest when the weather was a bit warmer...

    continued below
    Last edited by Fair!; 02-22-2018, 06:51 PM.

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above

    WHITELINE SWAYBARS

    We ordered these in a package deal with the coilovers below, but they were always on our short list. We made a point of adding these larger swaybars to this car now so we could design around them for our long tube header V8 kit, too. Matt's blue BRZ also used Whiteline adjustable swaybars on our original test 86 back in 2013 (he got some pre-production bars back then, which we worked with Whiteline to tweak the front slightly for production).



    On Matt's blue BRZ (in the pictures above and below this paragraph) we used the smaller of the two current optional Whiteline bars for the 86: the 2-point adjustable 20mm dia. front (BSF45Z) and the 3-point adjustable 16mm rear (BSR53Z). We installed these and MCS TT1 coilovers, which we developed the lengths for back then. Ideally we would have put the bars on first, then tested with those, then added the MCS coilovers. But as is often the case, the bars were installed at the same time as coilovers.



    Not much has changed on swaybars since 2013 from Whiteline, but this time for our red FRS (shown below) we chose the fatter 22mm dia front (BSF45XZ) and larger 18mm rear (BSR54XZ) bars, with Whiteline end links. Since our plans in the future include very wide tires for this car, we figured we would need the most roll control as possible. Also, the Whiteline coilovers we installed on our FR-S have less spring rate than our MCS TT1 install on Matt's BRZ (more on that below).



    The rear swaybar is relatively easy to swap. Off comes the old end links, then body mount bushings (above left), and on goes the new Whiteline unit. The swaybar mount bushing shell is re-used but a new black "elastomer" (they don't use "polyurethane") sized to the Whiteline's bar diameter is used. We're not going to leave well enough alone there, though.



    Next we checked for bind - and in this video I note that the rear was a little bound up in the black bushings. Normal, and it was easy to shim that out. The goal here is to reduce bind in the mounts, and if you cannot rotate the bar with pinkie finger effort, it needs adjustment. After the bushing mounts were shimmed they were marked and removed - then drilled for grease zerks. Drill through the metal bushing shell, through the new black bushing, and stop at the swaybar. We want to be able to get grease to this inner surface, where the bushing meets the bar. A threaded grease zerk was added (see above left). Then it all went back into the car and the Whiteline swaybar reinforcement tubes were mounted (shown in gray, above right). Last but not least the gold colored lateral collars were installed inboard of the two mounts, to keep the swaybar centered.



    Up front it was much of the same - mock-up the bar with the new black bushings in the stock shells, then rotate and check for bind. Shim to adjust bushing pre-load, get it to pinkie effort. But then the grease zerks, which I deem critical to all rotating bushings that aren't metal to keep them bind and squeak-free long term, were impossible to drill and tap in the car. Before the bar came off for drilling we customized the front end links to fit the Whiteline coilovers. This was due to a change in the end link bracket mounting height, which we will share all of this with Whiteline so they can offer the same fix we built. We will include the new endlinks with these Whiteline MAX-G coilover kits for the 86.



    The whole lower assembly of swaybar and chassis mounting brackets was removed and the shells were drilled and tapped on the bench. Then it all went back together. Adding grease zerks and shimming the swaybar bushings, plus some video portions I made, gobbled up 4.5 hours on the "swaybar install". Again, some of this is development time we use to help Whiteline get a more developed MAX-G coilover kit and to make our instructions, but be prepared to spend 2.5 hours for a "fast" install and 4 hours for a "grease zerked and shimmed" install on an 86. Read below for more.



    Don't forget to check out this video we made during this swaybar install, which is on our Youtube channel. This "removing bind" in the bushing trick applies to ALL cars, and should be the basis for ALL swaybar installs. We have to shim and grease zerk swaybars 99% of the time - no matter the car model or brand. If you add bind in suspension bushings you are adding problems with effectively additional/uneven spring rate, and funky handling.

    WHITELINE COILOVERS

    On our test S197 Mustang we used 4 different coilover kits in 5 years (AST 4100, AST 4150, Moton Club Sports, MCS RR2), which helped us prove some parts and helped some manufacturers we work with tweak their designs. When it comes to coilover shocks to fit this 86 chassis we now have 4 brands and many options to choose from, and it was tough choosing the first one to start with. Like our other long term test cars these might not be the last set this car gets.



    The Ohlins R&T kit (above left) was tempting, and this car might also get the MCS RR2 remote doubles (above right) in the future for use with much wider/grippier tires. Right as I was about to order a set, the Whiteline folks sent me info on their new MAX G single adjustable inverted monotube kits - and of the first 6 kits they offered, the 86 was one of them. We got one of the first production kits in late December 2017, with the goal of giving them our feedback and to get some track test laps on these in our 86.



    The front struts are Dutch built inverted monotubes with a single adjuster (on the bottom, 12 clicks) and massive 50mm upper shafts (with 46 mm pistons inside). Big, beefy struts that should take a lot of abuse. Inverted struts are built upside down (the piston is inside the 50mm chrome shaft section) and offers increased rigidity, especially when extended. We went with their included 258 #/in springs and added Vorshlag camber plates with 60 mm perches, of course.



    There is a slotted hole in the front strut mounting flange that allows for additional camber, which is set by using the machine insert, slugs, shown (above right) to keep it from sliding under load. This kit came with centered and offset slugs. Now I'm not a big fan of this way of adding camber as it EATS inboard wheel room (as you slide the spindle closer to the strut), so we used the centered slugs. We can get ample camber in our much easier to adjust top mount instead, but it is a nice feature (MCS also does this).


    The Whiteline MAX G coilover kit for the 86 comes complete with everything above, and can work with OEM top mounts

    The rear shocks are standard 14mm shaft monotubes, with the knob on the top. This is easily accessible from the trunk (if you don't have a battery sitting on top of the shock tower) to adjust rebound over 12 clicks. Again we wanted to test with their included 258 #/in springs but found an unusual shaft configuration so we are machining some parts soon to allow use with our spherical rear top mounts - we kept the stock mounts in place for the first tests.



    The original 2013 Scion shocks were pretty tired but the car still rode well on the street. The stock springs on the 2013 FR-S (here) and 2013 BRZ (here) are pretty dang soft. These seemingly soft-ish Whiteline springs are 100% stiffer up front about 25% stiffer out back (we usually start at 450 #/in front and rear with MCS).



    Saving weight going from OEM struts to coilovers is normal, but in the case with inverted units it wasn't as much as we'd normally see. These Whiteline units are heavy duty.



    Again, the damping adjustment knobs for the front struts (above left) and rear shocks (above right) are fairly obvious, and easily accessible. The front can be reached by turning the wheels to full lock and reaching underneath the strut. We set them both to +6 from full soft for our initial ride quality testing and they rode pretty well. Firmer than stock of course but not jarring.



    Compared to the stock ride heights of 14.5" front and rear, we have lowered the front 1" and the rear .75". This 13.5" F / 13.75" R ride height gave the shortened Whiteline MAX-G coilovers the deal bump/rebound travel ratio: 3/5ths total travel in bump and 2/5ths in rebound, from ride height. We spent a good bit of time testing this and coming up with these numbers - it wasn't some "it looks good" setting, it was what these shocks worked best at. The before/after suspension setup sheet is here.



    After the ride heights were set I asked Aaron to go back and measure the lower perch height with the included 258#/in springs to give people a reference for setting up the shocks before they install them. This will save someone a bit of time getting the initial ride heights set, if you use this set of coilovers, springs and our camber plates.

    The final install and ride height testing took 3.4 hours, not much more than a typical coilover install. Again we paused a good bit to take pictures and verify bump vs rebound travel to get ideal stroke distance, take pictures, etc.



    We checked front camber at "max negative" with the coilover version of our plates at the new lowered ride height and it jumped massively to -4.4° up front. The coilover camber plates can get a bit more negative camber travel, for sure, but a big chunk of the change was the lowered ride height.



    That's a bit much for a dual purpose alignment so we took it down a bit to -3.5° front and -2.2° rear camber, with zero toe up front (for street use) and 1/4" total toe-in out back (helps with turn-in). Caster was +7.1°, which is ideal. Next up is a track test! We want to see how the car stacks up against the baselines stock test and the followup test with camber and the Powerbrake fronts. We finished this work December 18th and my plan was to take the car to MSR-Cresson the 20th... then the weather turned to crap and it was cold and wet. I could go the following Friday... then I got the flu, which knocked me out for the entire Christmas weekend. Since then the weather turned sour and we've had unseasonably cold sub-freezing temps and the member days at the track are all running the wrong configuration for our testing.



    I found the next date that this track is running the 1.7 mile CCW course is on Jan 13th with APEX, a local HPDE group, and signed up in Advanced group. I'll get out there in a couple of weeks, drive several sessions, log some test data, capture some video, and post up another update. I'm hoping the shocks and springs help us find 2 seconds of lap time, if the weather gets back to normal.

    LS SWAP LONG TUBE HEADER DEVELOPMENT!

    Many of you reading this are expecting to see the long tube headers re-developed for our LS swap kit. And frankly I had expected them to be done by now, too. We had decided after the production header fixture was damaged last year to try a new header size and manufacturing method, so we ordered a 1-7/8" ICE Engine Works modeling kit back in Dec 2016. The kit showed up in late November 2017!



    We had made a dozen phone calls about this but there were production delays - which made for our own "production delays". This 1-7/8" diameter ICE kit is more appropriate for larger LS engines (and has no downside on smaller ones) and we have used it on three LS header builds in the last 6 weeks, including a prototype LS swap design already underway (BMW E36 RHD LS swap).



    It sucks that this delay pushed our 86 LS header re-development back but now we're ready to attack. As soon as we come back from the Jan 13th track test we will bring the FR-S in, yank the FA20 drivetrain, and start the LS swap with the header development on a fast track. The group doing the production work promised a faster prototype timeline, with CMM modeling and CNC bending. We're going to design these new headers to work around the stock front swaybar location (using the bigger Whiteline bar), which should save a lot of hassles for the people that have already bought our 86 LS swap motor and trans mounts.

    More soon!
    Last edited by Fair!; 01-28-2018, 08:06 PM.

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    Project update for January 4th, 2018: Well its been 12 months since my last update here, but we have been testing products, updated and developed a few new products, and installed a bunch of new parts on our 86 test chassis. New shiny suspension parts!



    This update covers camber plate testing, new swaybars (with some install tips), a brand new set of monotube adjustable coilovers, a new rear battery relocation kit, and we have started taking our car from FA20 power to LS V8 power. We're not there quite yet, but damned close. There have been some unbelievable delays with a header modeling kit that set us back on long tube LS swap header development, but that finally arrived and we have tested the tools with two new sets in the last 6 weeks. Our 86 V8 headers are next!



    We also got very busy here at our shop in 2017 - with big customer projects, other shop development cars, and other shop forum build thread updates have gobbled up my free time. I also currently have 12 cars, with half of them projects getting worked on or used for developing parts. We also have three different V8 swap development projects underway concurrently, I am trying to manage construction of a new building, and so much more. I've got lots of excuses for not posting this update sooner - let's just get caught up on the 86 project.

    MORE CAMBER PLATE TESTING!

    Some of this might be boring (or trigger someone who realizes we are a company that actually... sells things!) but product testing its an important part of all of shop owned cars/builds - and this car is no different. I literally bought this FR-S just to develop parts for the 86 chassis. Camber plates are the biggest item we make (it is why Vorshlag exists), and we have used this FR-S to test multiple variations of the 86/GD version, so I'm covering it here.



    We have been making camber plates for the GD generation Subaru Impreza for over a decade but we could not find a good way to make this design work with OEM diameter springs.



    Its a long story but it comes down to the fact that that "stack-up height" of the OEM strut top mount and spring perch is low, because part of the rubber strut top mount sits above the strut tower on these cars (see above left). Now there are some camber plate options for this chassis that move the entire camber plate above the top of the tower, but we looked at those designs and deemed them too compromised. There is lower strength and less overall camber adjustment that way, to name two negatives.


    Our testing can show when a design doesn't work perfectly, like these two early Subaru upper spring perch designs

    Everything is a compromise in motorsports - there is always a small trade off for veering away from the OEM design, but when the benefits outweigh the negatives we move a tested design into production. We developed an OEM upper perch setup to work with our GD camber plate back in 2008 (above left), but it did not work well in testing. We made another attempt in 2012 (above right), using Matt's blue BRZ, and again - it did not pass our rigorous testing. Finally in 2016 we made a radically different version of the upper perch and camber plate (below left) and tested that on our FR-S. This third version worked well in testing and went into production.



    As you can see from the two very different versions of the GD/86 camber plate we make above, the version for use with the OEM diameter springs (above left) has a different arrangement of the spherical bearing holder (including more parts), which sits on TOP of the plate. The version (above right) for coilovers has the bearing holder BELOW the main plate. We did this to reduce stack-up height - to not raise or lower the ride height with stock springs. With coilovers, ride height can be adjusted on the strut, so this isn't a concern.



    We have been producing this 86 camber plate for OEM springs for a while now and the one compromise it has over the coilover version is that the OEM version cannot get quite as much in-board camber adjustment - its a physical restraint of the top mounted spherical bearing holder. The main plate we are using still has additional positive caster built into it (a rearward offset) and we could have removed this to gain a hair more camber travel, but we found that our car had enough negative camber with this setup. And the added caster was deemed necessary on this car.



    Our FR-S was able to get -2.8° camber on one side and -3.1° on the other with the OEM springs, but we dialed it back to -2.5° camber - which is a common setting we shoot for on "dual purpose" alignments, for cars that see both street / track use with the same alignment.



    Back in September we installed our "OEM" camber plates on a 2017 BRZ, for a customer who is tracking it (above left). He come back after he got the car aligned and supposedly our camber plates "couldn't get more than -1.5° camber". We looked at the car and my "calibrated eyeball" told me it had at least -2° up front... as did our digital camber gauge.

    To verify my eyeball I paid for another alignment check at a shop that we trust and our shop manager Brad helped them align the car to max negative camber. Sure enough it had these numbers above right, -2.1°. So while it was a little less than our car, it was nowhere nearly as bad as his first alignment showed. Lesson: never blindly trust a machine, even if it has perceived digital accuracy. If it doesn't look right, get a second opinion (alignment test).



    Still, it was an intriguing situation - some cars with our "OEM" camber plates might also not be able to get the ideal -2.5° camber setting at stock ride height. So and Jason and I agreed to make a test set of plates with "no caster" to see how much additional negative camber this would allow. The test set above was built last September using an old prototype steel main plate that had no caster offset (from 2007), which we installed, then had our car aligned. It only gained 0.25° more camber on our car - not enough to make an all new series of plates, so we cancelled another "re-design".



    The result is - our OEM camber plate option does work well, adds a considerable amount of camber and caster, and for the casual track day driver this is the right option. More serious track and autocross drivers are going to replace the OEM shocks and soft stock springs (or lowering springs) for coilover shocks and stiffer springs. And as we know, when you lower ride height in a McPherson strut equipped car you gain more negative camber, too. When we lowered our FR-S on coilovers (shown above, read about below) we were able to reach -4.4° front camber with our production 86 coilover camber plates. That's huge camber. YUGE!

    REAR BATTERY RELOCATION

    Our red FR-S here is not just a suspension test mule but is slated for an LS engine swap, to help us finish development work for our V8 swap kit. We worked on a number of things this year to get this car ready for this swap. One thing we need removed from underhood is the factory battery - which gobbles up precious space in the right rear corner of the engine bay.



    The original stock wet cell battery was looking pretty old (4 years) on our red FR-S and started flaking out, causing the car to randomly not start. The "390 Cold Cranking Amps" wasn't exactly overwhelming for stock FA20 use, and for the V8 engine sporting 3x the displacement coming shortly, it was deemed undersized. It was time for a new battery, and I wanted it mounted in the trunk for use with the LS V8.



    The stock battery was 28.8 pounds, and you might expect our next move to be a swap to a small, lightweight Odyssey PC680. These small motorcycle sized gel-cell "AGM" batteries weigh exactly half as much at 14.4 pounds, so we could drop a few by swapping to this little unit. But you'd be wrong...



    Back the truck up! What is this big heavy thing doing on the scales? You guessed it - we're moving to an AGM Optima red top battery for this car. Why? Good question.



    First, is reserve capacity. With added mass comes added capacity. The itty bitty AGM (Absorbed Gas Mat / aka: "gell cell") motorcycle batteries we have used countless times over the past 14 years that Vorshlag has been building cars just simply have less capacity. They are great for race cars, but the major compromise is reserve. If the car sits for any length of time without being driven, the small discharge of the OEM computer and clock will drain a Odyssey PC680 - every car equipped with one of these in our shop is always on a battery tender.



    Look at the image above - it doesn't take a rocket scientist to understand why a smaller battery has less reserve capacity. You cannot go from a massive OEM sized battery to a little motorcycle battery and have no compromises. Look at the big factory BMW E46 battery next to the Odyssey PC680, above. Wanna guess which one has less reserve capacity? Now less reserve is not the end of the world, but if your car with a little AGM battery sits for a while and isn't on a trickle charger (like in an enclosed trailer between events), just expect it to NOT start. The fix for low reserve? A bigger battery. Which also works better for daily-driven cars like this FR-S, which Amy drives daily. When it doesn't start, trust me, I'm going to hear about it! This big Optima will prevent those little emergencies.

    The specs are another enough reason: Optima Red Top 34/78 series has 800 CCA, 50 Amp Hours of capacity. The little PC 680? Try 170 CCA and 16 Ah (the OEM wet cell / lead acid battery for this car was 390 CCA and 48 Ah). Plus moving the (now heavier) battery 10 feet to the rear should alter the front to rear bias decent bit - a good move on these front heavy 86 chassis cars. And adding more cable run from the battery to the starter soaks up voltage, which a bigger battery can better dish out. Win, win, win. The only downside: It gains some weight, but it is in the rear (which is always light on an 86).

    Alternatively SUPER SMALL little Lithium Ion 12 v batteries are the worst option available: sure, they are lighter (some folks use a 3-4 pound unit), but they have extremely high costs and absolutely terrible reserve capacity. All of the bad aspects of a little PC680, exaggerated worse. These were all the rage 3 years ago, and now "poof" - they are relegated to formula cars.



    Where to mount this big hunk in the trunk? For a one-off build we could cut a hole in the floor and hide it under the trunk carpet. But we wanted a more repeatable solution, so I asked my fab guys to think about OEM holes to key off of and make something that is a bolt-in. They did, but there were some compromises. The mount we used has an adapter they built that bolts to the rear shock mounting holes. Fine for stock shock use, but with coilovers it covers up the adjuster completely. Version 2 coming soon. The ground cable is mounted to a stud in the trunk, and we used the side posts of the dual post 34/78 series Optima, then and kept the plastic covers on the top posts.



    We ran a 00 gauge stranded cable forward from the trunk, through the little plastic trough that the OEM harness passes through, and into the engine bay. The images above show the routing - this was actually very easy to do, and the OEM routing of wires left plenty of room for this big hunk of copper cable.



    After a bit of machining and careful parts selection we have this positive and negative post bracket shown above, under where the factory battery used to be. The positive post is mounted via an isolator, of course, and then the main power leads land at this post. Nice and compact, should leave plenty of room for the remote coolant reservoir and ECM, when we do the V8 swap on this car. This install works, and is a good prototype from which we will eventually make a production ready battery relocation kit from.

    continued below
    Last edited by Fair!; 01-28-2018, 07:50 PM.

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  • warmmilk
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    Originally posted by Fair! View Post
    Yes, we are a dealer. Its a long story but Powerbrake is just now getting the application catalog out to dealers with pricing and car coverage. We here at Vorshlag are about to launch our brand new website in the next few days and will have listings there.

    [IMG]https://photos.smugmug.com/Product-Pictures/Powerbrake/i-pHcNBJM/0/M/B61G0177_3-M.jpg[IMG]
    Powerbrake X-Line X4ES 4-piston 325x28mm FRONT race brake kit for Subaru BRZ & Scion FR-S

    The X4ES front big brake kit for this FR-S/BRZ is $1995 for the rotors, calipers, brackets, lines and hardware. Pads can come from Powerbrake (+$275, in a number of compounds) or virtually any other supplier - they use common ISI pad shapes so you have over a dozen pad choices.

    Thanks,
    do they have a kit for the NC Miata?

    Leave a comment:


  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    Originally posted by warmmilk View Post
    do you guys sell Power Brake? You've put it on a few of your cars but I can't find it on your website... or any website for that matter
    Yes, we are a dealer. Its a long story but Powerbrake is just now getting the application catalog out to dealers with pricing and car coverage. We here at Vorshlag are about to launch our brand new website in the next few days and will have listings there.


    Powerbrake X-Line X4ES 4-piston 325x28mm FRONT race brake kit for Subaru BRZ & Scion FR-S

    The X4ES front big brake kit for this FR-S/BRZ is $1995 for the rotors, calipers, brackets, lines and hardware. Pads can come from Powerbrake (+$275, in a number of compounds) or virtually any other supplier - they use common ISI pad shapes so you have over a dozen pad choices.

    Thanks,
    Last edited by Fair!; 01-06-2017, 06:00 PM.

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  • warmmilk
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    do you guys sell Power Brake? You've put it on a few of your cars but I can't find it on your website... or any website for that matter

    Leave a comment:


  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above

    ADDING 5MM SPACERS AND LONGER WHEEL STUDS

    Like the BRZ wheel, the factory 17x7" FR-S wheel is very "flat" and the spoke design is not conducive to an easy big brake upgrade. We knew from our mock-ups that we needed a 5mm spacer to clear the larger caliper with the stock wheels, but most other wheels we tested needed nothing. We haven't planned on keeping the stock wheels for much longer but we did want to get at least one more track test in with the tiny 215mm tires and 17x7" wheels to show just how much lap time drop we could attribute to the camber and brake upgrade.



    The factory wheel studs on the 86 chassis are pretty short, and like most OEM fitments don't allow for even a narrow 5mm spacer. What you are looking for is proper thread engagement on the lug nuts, and the rule is "one diameter worth of threads". That means that on our M12 studs we need 12mm of depth of thread engagement with the lug nuts, after installing the spacer.

    We tested with the spacer installed above and and it looked like the studs would be to short. We counted the turns on a lug nut anyway, and it was 2 threads short, so it was time for longer wheel studs. This was something we covered earlier in this build thread, where we installed 65mm long wheel studs on the blue BRZ and an FR-S. But I'll show it in more detail here....



    The hubs are a unit bearing design that bolts to the front uprights, so those were removed (see above left). I snapped a quick pic of the 65mm studs we offer and have tested on these cars, both Subarus and 86 chassis cars alike. We also keep these 5mm thick, dual pattern 4 & 5 lug wheel spacers on hand. Being this thin they don't need or can even have an extended hub ring.



    Pushing out the stock studs from the hubs was easy with our 30 ton air-over-hydraulic press. Takes a few seconds for each one, with some spacer plates used to clear the raised bearing section of the hubs. You can see the OEM length next to our 65mm studs above, too.



    Installing the longer wheel studs was easy, just had to use a "spacer" to clear the raised section of the hub again. This spacer ended up being a second-hand bolt, but it worked fine. The splined ends of the studs need to be pressed in with a press like this, and "pulling" the studs in with a lug nut and impact gun is kind of a janky work-around. It always trashes the face of the lug nut, and always seems to cause minor damage to the stud during the install.



    With the studs installed in the front hubs (we didn't do the rears at this time, but documented that earlier in this thread) we then looked at the factory "closed" lug nuts. Those are usually a problem with long wheel studs because the added length can keep the lug nut from installing all the way. An open lug nut is preferred and the "extended seat" long reach M12 lug nuts we make for Subarus fit the bill. Bigger nuts are always useful...



    With the longer studs and 5mm wheel spacer installed you can see that the stock wheel spokes clear the caliper by about .200", which is double the clearance of factory 19x9" Mustang wheels to the factory Brembos, so no worries. We're gonna track test all of this properly, don't worry...

    MSR TRACK TEST, NOVEMBER 10, 2016



    Right about the time we wrapped up the prototype camber plate and Powerbrake install on the FR-S we had 2 other cars undergoing similar development - and all 3 needed to be track tested. We loaded up our NASA TTD prepped BMW 330 in the trailer, Jon drove the FR-S, and Jamie Beck brought his ST2 Mustang race car out to a member day on a Thursday in November.



    The weather was overcast but cool (58-72°F while we were running) and I took 5 test sessions that day, driving all 3 cars at least once and riding with Jamie in another. While it does take time and money to do these tests, nothing helps prove an upgrade like lap times at the same track.



    As with all MSR member days you have to wear full racing gear, head to toe, which keeps the squid factor down. We tend to go on Fridays but this time a Thursday test fit our schedules better, and we ended up having less traffic to work around, which was nice.



    All 3 cars we brought this day happened to have Powerbrake upgraded brakes, with the FR-S and ST2 Mustang both having new/untested setups. The Mustang had a prototype 6-piston front and 4-piston rear setup using 350mm rotors, which fit this car's capabilities since it has 18x11" wheels and 315mm Hoosier R7s.



    Jon and I each ran the E46 330 for a session and I put in one session in the FR-S, then 3 sessions testing and coaching in the Mustang. We ran the E46 back in March with NASA to a 1:27.604 best lap and this time I ran a 1:25.075 lap, for a 2.6 second drop in time. Even after dropping 250 pounds over the summer this BMW car is still 300 pounds heavier than the FR-S, but it does have a 245mm R7 tire on a 17x10" wheel, so it was making closer to 1.3g lateral grip.



    The in-car video above shows the best lap on the FR-S, plus a little clip where I tried a "2 in the dirt" line on another lap. I tried to take a certain fast corner "full throttle" and couldn't quite make it work with this setup, heh. Only time I have touched dirt in all of our test sessions here since March, but I had to try it.



    Back in our August 31st "baseline stock" lap testing I netted a best lap of 1:31.90 after 3 sessions of driving the stock FR-S. With the only changes being added camber and the Powerbrake front setup, I managed to drop 2.3 seconds netting a best lap of 1:29.630 this time. That's still with total CRAP tires that cost $50 each. That picture of the FR-S (above left) is after I passed the gutted E46 M3 race car on Conti slicks. Gotta admit, that felt good, but he was still warming up his tires. But still.



    Here's a listing of cars and lap times we have run at MSR on this same 1.7 mile CCW configuration:

    I will usually say that laps here under 1:30 are respectable for street cars, running under 1:25 is pretty fast, and under 1:20 is hauling ass. So the FR-S at a 1:29.630 is at least getting "respectable" now. Technically this would be classed as a NASA TTD car, so we're not exactly breaking any track records here yet, but we have barely started to prep the car. These tires are REALLY holding us back on lap times, yet still make 1.10g lateral grip. Not bad for fiddy bucks.



    We show the tire wear at the end of the track video, but these "new in August" tires had already taken a beating at the August and September track days without any camber up front - both "outside" tires (right side) showed plenty of wear. These tires were swapped front to rear before this event, and the front tire wear was was noticeably lower after getting -2.5° camber dialed in. Not surprising, right? Yet I was shocked at how much time we dropped with just "brakes and camber". A 2.3 second change is a big drop. Just encourages us to keep going and see how quick we can get this thing!

    WHAT'S NEXT?

    We still have an aggressive development plan for this car and I will show what we've done over the winter when we have some mods worth showing. The prototype OEM-style camber plate solution tested on our FR-S has already been released and we have production components for this 86 chassis. The 4-piston Powerbrake kit is also available.


    Do we go back to a tried-and-true MCS TT1 and 17x9" wheel setup just for lap time testing on our red FR-S?

    We're torn on what wheel/tire package to go with on Agent 86 next, and have debated this internally at great length. We know the 17x9" wheel / 255mm tire is good for an easy 3 second drop but do we pause there, or jump ahead to the BIG wheel and tire package we want to use with V8 power? Same goes for the coilover shock decisions - do we test a Bilstein PSS10 or MCS TT1 first, or jump to the MCS RR2 setup? Choices, choices...


    Track testing this current BRZ coilover + 17x9" setup will give us the data to fill in the gaps...

    To test that "next step" on track we are going to borrow Chase Reeves BRZ, which I mentioned last time. We used his car for PSS10 / Hyperco coilovers / Vorshlag camber plate / Vorshlag RSM testing and he loves the setup. He also has the 9" wide wheels and stickier tires on it, which we will try to take to MSR soon and get laps on. Will be a good metric of what to expect when you step up the mod ladder.

    More soon,

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    continued from above


    To minimize "stack-up height" of the camber plate and perch we used our "large diameter" radial bearing shown at far right

    After we had the main plate and bearing holder parts selected, Jason designed a super short OEM style spring perch. This billet aluminum part uses our unique sealed radial bearing in the perch, like all of our designs, which isolate steering loads away from the spherical bearing. The spherical should only pivot axially, and never rotating (or it wears out VERY quickly). This "large bearing" design also isolates the spring forces from the spherical, making it last even longer. You can see the perch installed above, during mock-up testing on Agent 86. We liked what we saw and then moved forward with the installation on the factory strut with the stock spring and rubber spring isolator.




    With the spring compressed the stock top mount and upper spring perch were removed and the prototype camber plate + perch were installed onto the strut. We arranged the new components to retain the exact length and compressed height of the stock spring/strut/top mount. This new strut assembly was then installed on each side.



    This setup would still allow for the added fixed amount of positive caster that our original GD design does, as well as considerable camber adjustment range. How much? The alignment rack would tell us. We were also able to use an existing, proven set of spherical bearing holder components - that don't have to shrink in size (and strength) to get every millimeter of adjustment, like some of the designs we see on competing 86 OEM plates. I wasn't willing to lose the massive strength advantage we have on our other designs, yet we could not afford to raise or lower the ride height with this OEM spring style design.



    The new setup was able to keep the same ride height yet add an additional 1.9 degrees of inboard camber adjustment and reached +5.6 to 5.7° of caster. The final alignment sheet is shown below.



    The max camber setting was -2.9° up front, which was more than we had hoped for, which was great. Initially we set this car at -2.2° front camber and 0 toe for use with the stock tires and suspension, for street driving. We drove it like this for a week and it made not a peep of noise or have any weird driving feel, so we tweaked it to up to -2.5° front camber for our next track test. With lowering springs installed the measured camber settings would be even higher - more negative - as they always do when you lower ride height on a McPherson strut car.




    Jason (engineer) and Ryan (CNC operator), shown above left, worked on this one together and took a lot of measurements. I wanted this design to be RIGHT with no noise, no raising or lowering of ride heights, and plenty of camber and caster. Donnie (above right) had these struts on and off the car several times for measurement, testing, alignment checks, post-test inspections, and more.



    After we had this design installed and street tested for a coupe of weeks we planned a track test at Motorsport Ranch track with the 86 as well as our TTD E46 BMW and a customers S197 Mustang race car. At the same time we added these camber plates we also upgrade the brakes. Because why not??

    POWERBRAKE FRONT BRAKE UPGRADE

    If you have been reading my build threads lately you may have seen this brand of brake caliper and rotor on other cars we have been working with. Powerbrake products are Motorsports grade brake caliper and rotor kits designed and machined in-house in South Africa. Their rotor rings are cast in Italy and machined in-house as well. The quality is second to none, but due to currency advantages for the US Dollar this is one of those few times you can "get more than you pay for."



    The first Powerbrake branded kit we installed was used on our BMW E46 330 (above) we built for NASA TTD competition early in the 2016 season. This kit uses their "large" 4 piston caliper and a reasonably sized rotor - which is designed to fit under most 17" diameter wheels.



    We have used these brakes on the E46 330 now for 5 race weekends or track tests and many hundreds of street miles with excellent results. We even had a double-driver weekend where Jon and I both drove it in back-to-back sessions for 2 days and the brakes never had a single issue. ROCK SOLID brakes that feel truly amazing. The difference in braking feel and confidence over OEM brakes really is indescribable until you drive on true Motorsports level brakes.

    Pad and rotor wear has been much lower than before with the OEM brakes and race pads, which means they are lasting much longer. We have extrapolated this over the long run, and it looks like the "cost-per-lap" of the Powerbrake setup will be lower than the OEM rotors & race pad expenses, and that's what many other users are seeing.


    Powerbrake X-Line X4ES 4-piston 325x28mm FRONT race brake kit for Subaru BRZ & Scion FR-S

    After using the big 4 piston front Powerbrake kit on the 330 I wanted to test out the Powerbrake solution for the front of the FR-S. Luckily they had just released an updated caliper design for 2016 called the PBX4, which uses two pads per caliper (unlike the 4 piston caliper on our 330, an older design that used 4 "padlets" per caliper). Above is the Powerbrake X-Line front brake kit for the Subaru BRZ & Scion FR-S. This features their new X4ES 4-piston caliper and 325mm x 28mm 2-piece rotors.


    The massive 4-piston Powerbrake X4ES caliper (at left) is 5 lbs lighter than the iron factory 2-piston FR-S front caliper (at right)

    The calipers are big beefy things made from of billet aluminum. This is more expensive than using a near-net-shape casting in aluminum, but it makes for a more rigid caliper - and this is what separates Motorsport calipers from even upgraded OEM aluminum calipers like "factory Brembos". This article by StopTech discusses "monoblock" vs 2-piece caliper designs like this, and their conclusions make sense.



    There are dozens of other features inside the calipers that make them better for Motorsport use as well. A quick look shows the stainless steel wear blocks, the gas ported stainless pistons, integral bridge, and the variable piston diameters which go into the engineered caliper solutions they produce. Vorshlag is working directly with the U.S. and South African Powerbrake engineer teams to help develop, test, and market their solutions for a variety of Asian, German, and a growing list of domestics.



    After the FR-S front brake kit arrived we took measurements, weighed everything, and mocked the kit up on our car for installation pictures.



    Many of the popular "big brake kits" (BBK) upgrades sold today are made to be HUGE, with rotors that reach 355mm or even 385mm in diameter. Those rotor sizes force drivers into 18" or even 19" wheel sizes. I could talk for an hour about wheel & tire diameters, sidewall heights, spring rates of tires, unnecessary mass, and tire selections in differing wheel diameters... but long story short, a massively larger diameter rotor can often be a determent on lightweight cars being used with sub-19" wheel diameters.


    The larger 2-piece Powerbrake 325x28mm rotors are only a hair heavier than stock

    As you can see in the pictures above, the Powerbrake rotors are indeed bigger, but in this kit they are not huge (and fit within most 17" wheels). These rotors manage heat with a thicker rotor, better venting design, and a lighter aluminum hat with (radial) floating hardware. All of these design features help improve brake feel and heat dissipation. Weight is lowered over stock, which is always a bonus, and between the caliper and rotor the Powerbrake system lost about 4.5 pounds per side over the smaller stock bits.



    Another major gain in braking stability and heat management are in the calipers. This "X4ES" caliper has a slightly larger pad surface area but a much larger chunk of billet aluminum makes up the caliper structure itself. This provides a more stable backbone to the caliper under extreme heat and clamping force, which allows for much less distortion and better feel.



    The FR-S/BRZ is a light (2650-2750 pounds) chassis and comes with a 17" wheel, and due to fender limits most folks end up with a 17x9" wheel and 255mm tire as the most common "wide wheel" used on the 86 with stock fenders. So in this instance the 4 piston caliper and moderate rotor sizes fit the needs nicely.



    Our car may or may not move to this popular 17x9" wheel setup, but our former blue 2013 BRZ test mule did definitely go with that size (in both D-Force and Enkei RPF1) on 2 different sets of aftermarket wheels. This is the wheel & tire what we recommend for most of our 86 customers, so we felt the Powerbrake kit made to fit inside a 17" wheel was worth testing on our latest FR-S.


    You sharp-eyed readers might notice that this rotor is on the wrong side - this was put on just for mock-up

    When Powerbrake sent us this demo kit for our studio pictures we test fit the kit to our car with green tape on all of the metal surfaces, to avoid scratching the calipers/rotors in case we didn't use it. But it looked so good, and with only a 5mm spacer we realized that we could use these with the factory wheels and tires, so we kept these for use on Agent 86.



    We also test fit these brakes (rotor + caliper) inside several other wheels one day, including a factory Subaru BRZ wheel, shown above. Like the factory 17x7" FR-S wheel, the BRZ wheel also required a 5mm spacer to clear the large Powerbrake X4ES 4-piston billet caliper. The other aftermarket wheels we tested did not.



    The popular 17x8" Rota wheel made for the 86 chassis was tested, and the common 17x9" fitments should fit as well or better - except for maybe the Enkei RPF1, which typically has terrible caliper and rotor clearance (they use a design trick to keep these wheels light, which gobbles up caliper room). We will test an Enkei on our car with the Powerbrakes soon and post that picture here.


    We love the RPF1 in 17x9" for the 86 chassis, but this wheel is notorious for poor caliper clearance

    After firming up the long term plans for this car, that included the big brakes, we purchased this kit for Agent 86. We felt that even with the big wheels and tires we are moving to that the car will always be light, and this Powerbrake kit should still fit our needs long term. Donnie had this front setup installed in about 45 minutes, with a brake bleed it was an hour of work. 100% bolt on job, no mysteries, and their instructions were excellent. Calipers come with temp strips in 2 ranges and rotors have 5 stripes of temp sensitive paint, to help you see brake temps. Legit.



    I don't like talking prices in these threads because then it all gets too "salesy", but this X4ES front caliper and rotor setup is remarkably well priced. If you want to know more, you know where to ask. These fit the car great, looked amazing, but we just needed to make the stock wheels fit the caliper...

    continued below
    Last edited by Fair!; 09-26-2018, 10:29 AM.

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  • Fair!
    replied
    Re: Vorshlag BRZ/FRS Project Development Thread

    Project update for November 17th, 2016: It has only been a few months since my last update in our FR-S/BRZ development thread, but we've done some upgrades and development work on our red FR-S (which now has a name), Amy has run it at an autocross and driven it at a Track Night in America event.


    Left: Amy has autocrossed the FR-S and tracked it. Right: Lap times from our Nov 10th track test (camber plates + brakes) were much faster!

    We have installed some prototype suspension parts and a new Powerbrake big brake kit up front. After that we aligned the car then I track tested it at MSR-C to see how much quicker it is from our original stock baseline (a good bit, actually), all while still running the stock springs/swaybars/struts/tires. I am kind of surprised at how ... excited I am to see this car developed, because it is the "anti-Fair" car - a light, under-powered momentum car with skinny tires.

    IMPRESSIONS AFTER 2 MONTHS OF OWNERSHIP

    I shot this 6 minute in-car "Test drive" video a few weeks ago after owning this 2013 FR-S for almost exactly 2 months. In that time Amy has daily driven this car a lot and loves it, and even I have been warming up to it a bit. It was lighter than almost any RWD Coupe made in quite a while, and having a light yet rigid chassis matters SO MUCH.


    Click here for 6 minute "test drive" video

    If you watch the video above I talk for several minutes about the FR-S/BRZ chassis, explain why I think "car people" should test drive one. I compare the 86 chassis to the NC Miata (same time period, similar costs, similar weight) but explain the reasons why the 86 is a better track car than the MX5. I include some data - weights, front-to-rear bias, sales numbers - in the closed caption comments as well.

    In the closing 30 seconds of the video above I give away a lot of the plans we have in store for this car, and a season of racing NASA TTD or TTC racing is probably not going to happen. If we stick to the plan we're going straight from stock engine to LS3, from 215 to 315mm tires. Because... America!



    The same day as the 0-60mph test drive video, I spent about an hour washing and detailing the FR-S, which was the first time I think that I have cleaned this car up. It needed it, and still needs more detailing, but we have a lot of things we will change on the body before we really worry about paint detailing.



    Stay tuned here for more development on this red FR-S. There is also a forum build thread detailing our Vorshlag Scion FR-S LSx Alpha Project, that I wrapped up recently after we finished work on this customer V8 car. That will be a way to show the various parts and systems we need to tie-into and develop using this car. Somehow I will merge that Alpha thread with the updates in this generic BRZ/FR-S development thread, after this red FR-S has a V8. Who knows, I might just post the same update in both threads? We'll see.



    Anyway, it was nice to spend a little time cleaning up this car and doing a little 0-60 mph test, to help get this project kicked off properly. If we are going to go crazy on this car, it does need a name...

    NAMING CARS IS SILLY - BUT OFTEN NECESSARY?

    I know a bunch of you reading this will roll your eyes when you see that we have named the red FR-S. I am doing the same thing here, but let me explain. So many times in the past when I would see famous car builders naming their project cars I would groan. How starved for attention do you have to be to "name" a car you are building, thinking it is somehow special enough and rare enough to deserve that?


    The world's first BMW E36 LS1 Swap build - our original "Alpha car".

    But over the 12 years that I have been building up Vorshlag we have had to concede that, yes, sometimes you need to name your build. At first I would inadvertently call a build an "Alpha" or "Beta", just to show that it was the first or second of a type of V8 swap on a chassis. Like our "E36 Alpha LS1" (see above) was the first BMW ever built with an LS1 V8, way back in 2002, and was known for many years as "The Alpha" in BMW circles.


    Left: Our NASA TTC build on a 1992 Corvette was "Project Dangerzone". Right: My beater shop truck is "Truck Norris"

    After seeing our first "million view" thread after building that car, my wife pointed out that we need to keep naming our cars, even when I fought it. She is the one who came up with most of the names of subsequent shop car builds, and its always tricky to do without sounding silly. We've had some memorable ones such as: Jack Daniels, Dangerzone, Truck Norris, the GRM E30, and "The Red Car", to name a few.


    Chainsaw (L) and Chainsaw Mouse (R) are being replaced by Chainsaw Massacre, a monster E46 M3 V8 build for a customer

    Sometimes naming a car is a quick shorthand way for us to refer to one of many cars in our shop during the build period, or to quickly describe one of many cars from the same customer. We've built multiple cars for some customers, and one of them started naming each of his cars, which helped us when we conversed with him about multiple on-going projects: Chainsaw, Chainsaw Mouse, Chainsaw Massacre are three of his we built in a row. Even our own shop owned vehicles have become too numerous to describe quickly: We own FIVE different E46 BMWs right now, so a quick name is easier to use than "The white 330 Coupe... no, the other one!" We called our red TT3 Mustang GT "The Red Car" but we have 4 different "red cars" right now, so we have had to expand on that. And maybe Amy thought of a good one this time...



    There was a spy comedy show called Get Smart, released before I was born, that ran for 5 years, and had several follow up movies as recently as 2008. The original show was created by Mel Brooks and the main star was Don Adams, who played Maxwell Smart, Agent 86. Most of you reading this know that the FR-S/BRZ/GT86 models are referred to as the 86 chassis globally. And that is where she came up with the name for the FR-S, Agent 86, and just "Max" for short. We're going to have to find a place to mount the shoe phone...?



    So yea, this FR-S is called Agent 86, another car with a corny name. We don't name every project we build but only the ones we feel are worth it. Hopefully this build will live up to the hype.

    TRACK NIGHT at MSR-C, SEPTEMBER 27, 2016

    We brought the FR-S out to this SCCA "Track Night In America" event, where Amy got three track sessions. I barely paid any attention to the FR-S that night as I was performing three separate track tests in the Focus RS we are using for suspension, wheel and other development work so I was busy. We were swapping wheels/tires, changing settings, and had all manner of cameras, data loggers, and timers to keep up with in the RS.



    This new AWD 300 hp Focus RS is a bit of an understeering mess and required some pretty drastic suspension changes before we got the car to "calm down" on track and quit eating front tires. We have done several tests at MSR with this car, even back when it was bone stock (where it ran a 1:27.4 in July). With the coilovers & camber plates it dropped to a 1:26.212 on the standard 235mm MPSS street tires, which was the 1st of 3 tests we did that night.



    It dropped another HUGE chunk of time on the 275mm RE71R Bridgestones, shown above, running a best lap of 1:23.510 that night (which is only 1 second back from what I ran in a Corvette C6 Z06). So from stock to "better suspension + better street tires" we found 4 seconds in the Focus, which is a massive drop in lap time. Yet we have found more than half that much time drop in our FR-S just with camber plates and brakes. Check out the latest track test in this update, below.



    This night wasn't about testing in the FR-S, as nothing had changed since we put it back to "refreshed stock form", so I didn't take any laps in it. Amy had three trouble-free sessions in the FR-S, but the front tires were starting to show some noticeable outer shoulder wear. Up to this point we have done ALL of our track testing on the same CCW 1.7 MSR course, so the right side tires are taking a beating, but especially the right front. The tread blocks were starting to chunk on that corner, just like we saw on the Focus RS. She ran some low 1:33 laps and had a blast, getting much needed seat time in the Scion.

    AUTOCROSS WITH SCCA at LSP, October 23, 2016

    Amy ran "Agent 86" in bone stock form at this autocross, her first in the red Scion. She ran in the local Women's class with a C Street PAX and had fun on the same CHEAP 320 treadwear 215mm tires. I was working at the shop that day, but she wanted to get one autocross event under her belt while it was still stock, to see the difference before and after. The more testing we can do along the path of mods we have planned, the better.



    These cars in stock form are "fun" to drive, but they are not exactly fast. The tires they come with from the factory are a HUGE limitation, and the soft spring rates don't exactly make for flat cornering. Amy has a lot of experience autocrossing and has multiple SCCA National Championships under her belt, so her overall ranking in PAX will be a good metric for how fast and the car is at the moment - or not.



    This was a typical course for our SCCA region, and she said she had a lot of fun slinging the car around. C Street class allows the dampers, swaybars and tires to be changed (any 200+ treadwear tires on the stock sized wheels).



    Since this FR-S was still on the stock dampers, swaybars and tires, it would be handicapped pretty hard, but it is just where the car happens to be right now. The images above (which were purchased from two different photographers) show the score: lots of body roll, positive camber on the outside front tires. Damn this car needs some camber and spring rate, in a bad way!


    Click here for the in-car video from Amy's best autocross run in stock form

    Her runs on video all looked pretty spot-on to me, and she said it was easy to push the car to the limits, but that "the tires were CRAP". She had clean runs all day and placed 3 out of 4 in the PAXed Women's class. Jen Maxcy was in a proper STX prepped BMW E36 328is in the same class and was 4.5 seconds head of her times, so the lack of tires and class prep definitely showed here.



    Amy placed 68th out of 151 times in the overall PAX standings, so we have a long way to go before the car is setting FTD or Top PAX at autocrosses (3.6 seconds back from Top PAX time). We figured as much, and while SCCA autocross classing won't play a real part in this build, it is a good metric to look at for overall competitiveness.

    PROTOTYPE CAMBER PLATE FOR USE WITH OEM SPRINGS

    As promised in my August update we wanted to use this red FR-S for development of a new camber plate design that works with the OEM spring diameter. We were unsure of how to go about this design but started with a handful of existing parts and designed a few more to see if we could make something that fit the tight constraints of the 86 chassis as well as the OEM spring limitations.


    Left: Existing GD/86 plate for coilovers. Right: prototype 86 camber plate matches factory stack-up height, for OEM spring use

    Our existing Subaru GD / 86 camber plate design (above left) works great with coilover springs with inner diameters of 2.25", 60mm or 2.5". We've sold hundreds of sets for these two Subaru chassis over the years but the camber plate + upper perch design is tough to replicate in the same space as the "short envelope" that the factory Subaru top mount + OEM upper spring perch fit inside.



    The trick that Subaru pulls on many of their strut top mounts is to move the mount above the top surface of the strut tower sheet metal, and then make the upper perch domed so that it sits higher as well. These two aspects gain them some added bump travel, but it makes it difficult to replicate in an aftermarket camber-adjustable top mount design.



    The image above left shows the amount the factory strut top mount "pokes" above the strut tower. The image at right is the bare tower without a top mount or strut installed. The round opening is rather large, and the trick we used to match the stock bits was putting the spherical bearing holder above the main camber plate, which gains some travel and keeps the stack-up short. We did so knowing that we would lose some camber travel, and thought we might have to make a unique main plate that lost the positive caster offset in our original GD / 86 camber plate design.

    continued below
    Last edited by Fair!; 12-04-2016, 06:06 PM.

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