[rbahr]

Hi All,

I picked up a 2020 M2C recently as track / road car. This means that I will leave the car registered, but will set it up as a track car - not full craze, but 'good-enough'

To help explain my point of view, I instruct with Porsche, BMW and a few others silly enough to let me. I am also coming from:





Which is a track-only GT3. Full motorsports suspension (Porsche RSR, Grand AM, and some Cup Car stuff - the real deal). Both a hugely expensive PITA and truly fast car. Problem is that I want to simplify my life a bit and the GT3 was going in the other direction. This car was easily $1100 a day to track... Being gainfully unemployed AKA retired, also really didn't help! I also have built many motors and transmissions and suspensions over the years, got a lift and have yet to meet a tool I didn't want - to my enormously patient wife's credit. I have also spent some time in serious race shops, ($200k+builds) so against my best wishes, actually learned a few things! This simplification things means not wanting to build my motor or tranny for some time - BTW JUST the gasket set for a GT3 is $1400, the transmission uses $400 bearings - LOTS!

So earlier this year, I did some research (being an engineer, that sorta comes naturally, perhaps to much so!) and picked up a M2C which at the time was perfectly content driving around town! I bought the car in Ann Arbor MI, flew out there and drove home with a friend.

1st impressions driving the car home:[/LIST]

• [SIZE="4"]
• This car has a REALLY small gas tank.
• This car makes stupid sounds IN THE CABIN
• This car is really HEAVY
• This car has awful steering
• This car is FUN
• This car is dangerous to your license - easy to find yourself cruising at 90MPH

Back to that engineer thing. The owner's manual is total rubbish - does not even tell you what kind and how much oil - important later, no location of fuses, really nothing useful, but lots and lots of warnings, kinda like don't hit yourself on the head with a hammer, cuz the hammer will get messy!

I started looking for proper service manuals, and yep ya need to get a (pirate) copy of ISTA+, and a different piece of SW for parts list.

We get the car back to MA, and I look for a dealer that won't void the warranty when I do simple stuff - suspension, seats, belts, brakes, etc. Not so easy, a lot of these guys are not my friend, they do like my CC though. I find someone I (think) I like, who finds me amusing - being 'older than dirt' in a young person's car helps

I get the various fluids I will need to start from a known good place, put the car on a lift and change the fluids. Turns out that BMW uses one-time fasteners all over the place just why? Not having a stock of these fasteners (yet), I torque things down, and skip the angular addition. I also install the big Alcon front brakes with respectable pads (bigger than some any way). I went with the 24mm pad size, as that might make consumables a bit cheaper in the long run.

I do my 1st event: this is is Club Motorsports in Tamworth NH. I am not expecting much, I never even aligned the car, all I did was put on a set of pilot cup sports, and drove there (first time I JUST drove to an event in many years). I was there less than 2 days when my windshield cracked, and I am leaving for LCMT in a week and a 1/2 Big scramble ensues, I find a windshield, and get it installed with 2 days to spare.


TAKEAWAY:

Not sure who at BMW programmed this car, or why they have the word 'Competition' in the title... But the steering is still awful, and the ABS is awful, and the rear diff is awful, and all other nannies are just... I get some recommendations for a coder, and he helps (a LOT).

I decide to share the car with my buddy who helped me get it home, and we leave for LCMT a couple of days later! Once again I DRIVE there! Hmmm, what could go wrong, I left the fun-flats at home, I DID get a spare tire...

We get to the tracks, and I am starting to like this thing, but BMW to the rescue again We destroy the front tires in a day and a half. Come to find out that the is no front camber adjustment on this car - no surprise to most, but I missed that memo. Granted that I had yet to do an alignment, but...

Now prior to all this fun, I had bought all the bits I was going to need (at least most of them). So I had my next event at WGI in 2 weeks. I install the shocks and front bar, and decided to hold out on the rear bar as it look just a bit involved to install. My car being in full droop on the lift, AND BW not really making it clear that the OEM bar MUST be replaced to work with these shock, was just somehow apropos! I then spend close to 10 hours installing the MANDATORY rear bar, corner balance it, and get the car aligned. And we are off to WGI.

This time I decide to tow the car as at LCMT I had a rather green (being nice here) driver spin in front of me (with an instructor in the car), and FORGOT to hit brakes and clutch. He was ~ 20ft in front of me when he spun. I headed to where he was, expecting him to be elsewhere, and he was, until his car started rolling backwards, I managed to stop with feet remaining. It would have not been fun to need to flatbed a car home across the border!

I get to the Glen, and put ~ 400 miles on the car, and I really enjoyed it.

I know I seem to be complaining a bit here, but I was really expecting more out of this car. I have had an E36 M3, and an Euro E24 M6 - all cars I enjoyed! All this said, I like the car, I have started to address some of the issues, and it still has a warranty! I still have a couple more events left this year, and I do need to be patient and realize that this is a work in progress.

Ray

[PackPride85]

I didn't have to read past the part about coming from a GT3 to know you would be disappointed. I consider most M cars "track ready" for casual days but certainly not setup from the factory for competition (yeah some irony there in the m2c marketing). The electronics are all programmed in a way to balance more regular street driving over aggressiveness for track. Your coder probably updated everything to the "CS" model parameters which definitely helps.

That being said if you spend some money it can be a decent competition track car while still maintaining street manors, but it's never going to get to GT3 level. Same as GT3 will dominate on track but can't really make it a good street car. Really just depends on what you're looking for which sounds like the former (easier on street with decent track capability).

[bentom2]

It won’t be totally transformative, but the front torque arm bushings are big soft rubber pieces that add to the isolated steering feel. Changing them for ball joint type bushings made the steering feel a bit more direct. Enough to be worth it. If you don’t have a press, Turner sells their version preinstalled in new OEM arms. Impact on NVH was minimal.

Rear toe arms add some noise, but in addition to allowing more range of adjustment for toe and camber, they also seemed to calm down the rear end under heavy braking.

Getting however much camber you can tolerate into the front end with camber plates obviously will help preserve your tires, but also makes a huge difference in front end grip. The camber plates added a bit of road noise, and some impact harshness over sharp hits like expansion joints.

Once you have a feel for the car, work toward turning DSC off. It’s garbage no matter how you code it and will hold back an experienced driver, while also accelerating brake pad wear.

I haven’t done anything about the diff yet, but I understand there are options.

Once you get the alignment sorted and have some front end grip, I suspect you’ll want seats and will realize how soft the suspension is.

That said, ~80 track days and 40k total miles in on an OG M2, progressing to an advanced pace the last couple years, I have only had to change fluids and consumables. My first part failure is a hydraulic motor mount that sprung a leak recently. The comp has better cooling overall so should be even better for long term reliability.

Pace is about 10-15 seconds slower than the better driven stock 991 GT3s that come out. 996/997 are much closer. GT4s are 5-7 seconds quicker. All on a 2 minute track with a couple long straights that the Porsche GT cars can really capitalize on.

Anyway, probably none of this is a revelation. After all of the above, I have a fun, reliable track car that I enjoy at a total cost I’m okay with, but it’s still heavy and slow if your reference is the newer Porsche GT cars that dominate the advanced PCA run group.

[rbahr]

Thanks, I am sitting on more parts. I have seats and belts, but need a half-cage or harness bar. My general rule of thumb is >140mph requires a cage. With the car as it is, I was seeing 145mph+ at the back straight at WGI.

Random thoughts:

With my 1st outings, I was literally 10-15 seconds off my GT3 pace at tracks I know well.

Bentom2: I will likely change out the rubber bits you mentioned, and I am ordering the CS Racing motor mount inserts to tame that down a bit. Also, where the GT3 really shined was the corners, I could out brake most cars, and be hard on the gas very quickly.

I will also be using a square setup and running 275's - with some non-slick tire choice

The person who did my coding (alex@alpinemss.com) did a pretty good job with the brakes / ABS, but that is with just moderately aggressive tires. Not sure what I will end up with, but should be interesting.

[DRLane]

You can absolutely build these to GT3 level. Of course It'll lose most of the street qualities that people adore.

[bentom2]

Originally Posted by rbahr

Thanks, I am sitting on more parts. I have seats and belts, but need a half-cage or harness bar. My general rule of thumb is >140mph requires a cage. With the car as it is, I was seeing 145mph+ at the back straight at WGI.

Random thoughts:

With my 1st outings, I was literally 10-15 seconds off my GT3 pace at tracks I know well.

Bentom2: I will likely change out the rubber bits you mentioned, and I am ordering the CS Racing motor mount inserts to tame that down a bit. Also, where the GT3 really shined was the corners, I could out brake most cars, and be hard on the gas very quickly.

I will also be using a square setup and running 275's - with some non-slick tire choice

The person who did my coding (alex@alpinemss.com) did a pretty good job with the brakes / ABS, but that is with just moderately aggressive tires. Not sure what I will end up with, but should be interesting.

I have a set of what I guess are reproductions of the CSRacing inserts from Bimmerworld that a buddy and I will be installing this weekend along with new motor mounts. I’m hoping that helps with the durability of the hydraulic mounts, but would accept getting the powertrain locked in place a bit more too.

I finally broke down and did the 1/2 cage, fixed back seats, and harnesses a few weeks ago, and was able to get a few days in right away. What a huge difference. I had resisted this because I liked the option of carrying 4 wheels and tires in the back, but I haven’t actually done that too many times, and as my pace has picked up, I was feeling less comfortable in Schroth Quickfit Pro harnesses and Recaro Speed seats from both a safety and support perspective. I think I can get three wheels in from the trunk and put a 4th in the passenger seat if I really want to carry a set.

There’s no substitute for having 55-60% of vehicle weight over the rear tires. Makes me jealous when I close in on a Porsche in the corner and they just rocket out in a way that I can’t match.

[dvas]

Originally Posted by rbahr

I know I seem to be complaining a bit here, but I was really expecting more out of this car. I have had an E36 M3, and an Euro E24 M6 - all cars I enjoyed! All this said, I like the car, I have started to address some of the issues, and it still has a warranty! I still have a couple more events left this year, and I do need to be patient and realize that this is a work in progress.

Ray

Feel and outright performance may be two different things here.

Leaving feel alone, the M2 is a pretty capable platform for tracking given its price and orientation towards street comfort. Turn all the nannies off (I agree that the ABS is junk, but I find the steering precise if lacking the hydraulic feel) and do basic mods to have some fun. For reference, a very modestly track-modified but well driven M2 on aggressive street tires can lap WGI sub 2:10, LRP sub 1:00, Palmer sub 1:48, Thompson sub 1:20, etc. Sure, it's not GT3 (with a good driver) speeds, but it's also one third the price - and anyways, how many of the PCA guys are hitting those kinds of times

Also, in terms of reliability, 60+ events on my 2017 and no issues, nothing to fix/replace outside of consumables.

[DRLane]

Y'all should probably take a look at OG Shark M2 build if you're not familiar for inspiration.

2:21 at COTA in >3500lbs purpose built but streetable M2, is 991.2 GT3 fast. Point is you can build a very formidable M2 if desired.

Also the Supra and M4 are running neck in neck with Porsche in Pirelli GT4 series. Obviously both those platforms don't benefit from the rear weight bias.

[CSBM5]

Surely you're tracking with DSC fully disabled? I don't identify with the statement about the LSD being awful. Awful in what way (with DSC completely off)? To contrary, I've found that it's programming is nicely done (if you're not familiar with it, it has a fast electric motor that controls LSD plate pressure varying from 0% to 100% lockup using multiple variables as inputs) -- one example: it's always near or completely open on low speed corner entry making for really nice turn-in (as opposed to adding understeer like a "dumb" LSD is typically doing, depending on ramp angles and static lockup torque) while at the same time it's "there and waiting" for you moments later when you need it putting power down on track out (as one of many examples). Now I'm comparing it to static mechanical diffs (i.e. typical multiple plate clutch LSDs) and a Visco-lok LSD, and it is far superior in my experience to either. Those are age old "two mechanical variable" LSDs (i.e. left/right tire speed difference, torque input to diff).

I spent about four hours on the Michelin 1/2 mile skidpad when my M2C had just covered break-in miles less than a week after buying the car back in Sept 2018, and I was really impressed with the LSD as I put it through its paces whether it was outright continuous high speed (~60mph) drifting or, on the other side of the coin, going for fastest lap time trying to hold the car on the circle at the limits of adhesion all the way around multiple times. Anyway, that was a great introduction to the M-LSD programming, and I can't say anything but impressive comments about my experience.

Perhaps we're beyond these basics and you're having some issues with the diff not providing the proper locking you expect under some condition(s)? If so, I would code scan the car as a first step. If no codes are shown and there is some problem with your diff that's "out there" in the performance envelope (i.e. not something normally exhibited during street driving anyone could experience), it's very hard to get any warranty coverage from BMW (much less find any person who will be able understand the conditions you describe that show the deficiency).

Give the steering time. Don't write it off completely. My first (and even sometimes still feeling!) is similar to yours (mainly since I often drive my E90 M3 with really nice feedback HPS). However, that day I spent on the Michelin pad early on with the M2C allowed me to develop a feel for the EPS and hunt out what it can do in terms of communication, and importantly what that communication feels like (it's different for sure from a nice HPS!). I spent a lot of time taking the car up to/at/just over the limits of the front tires on the pad (really nice environment to continuously evaluate something like steering feedback by driving just under/at/over the tire's limits continuously around the pad at speed), and I was able to develop a "feel" from the EPS of how it responds around the limits of the tires. It seemed "hidden" compared to a nice HPS for sure, but I could sense the decline in self-aligning torque as you get right near the peak of the tire cornering force curve. It did feel a bit numb right at that point and just over the peak grip point, but it was still providing feedback...just muted and much "different" than what I've been used to for decades also (been tracking cars since the 1970s). When I get in the M2C after having been in the M3, I mentally shift major gears in my brain since three main things are so different between these cars (torque curve and magnitude, LSD response, steering feel).

[allinon72]

Based on near universal praise for the car, peoples expectations have reached a point where they are expecting it to perform like a purpose built track car. It is not. It's a fun street car that can do some light track duty.

[OG Shark]

Tough to compare an F87 to a GT3. The M2 is more of a street car that can track while the GT is more of a track car that can street. With the M2's more street bias there is always going to be more compromise in the platform than the GT3. Tracking a stock F87 is going to be no where close to the same as a stock GT3. It just inherently needs more love in order to be really dialed in on the track. Also they are considerably more budget limited then what the GT3 is in design. Makes a huge difference in how they track. The good news is though that the potential is there for the M2 but you have to help guide it there instead of it being delivered to you from the factory.

I do want to say too that although the platform is not exactly dialed in for the track out of the box - it is still can be a lot of fun in stock trim. During the benchmarking of my oem M2C had an absolute riot on track. The car is still pretty nimble & playful and it was fun trying to squeeze every last bit of time my skills could get out of the car.

I will say that it can be hard to go from a track dedicated car to a street car (especially stock) and not be disappointed at first. Even going from my race cars to the M2 takes a bit to get readjusted to - and my M2 is current GT3 fast (and still very streetable too).

[rbahr]

Thanks for the feedback all.

CSBM5: I am now turning everything off, and I got ABS, rear diff, and steering coded - so better. I absolutely need more seat time in this thing, but I initially found the on center steering feel to be vague or numb. The GT3 LSD was 'improved' and running motorsports clutch disks.

DVAS: When figuring out what car I wanted, I was targeting sub 2:05 at WGI. With the M2 as it is I was seeing ~2:13 recently. I had considered the Corvette, but as a buddy said 'It is a digital car trying to look analogue', and having instructed in a number of them, it really didn't do it for me.

OGSHARK: absolutely correct - " The M2 is more of a street car that can track while the GT is more of a track car that can street.". I will read through your build to see what you did.

All: I need to remember that I made a choice to no longer wrench on my car for 2-3 hours for every hour driven. I am also needing to avoid a crazy slippery slope, but I still need to tighten up the steering and shifting, and GET MORE SEAT TIME!

I will be going to a square setup for rims and tires, so that will change a lot of things, and I will need to figure out / dial in the shocks.

Does anyone have any recommended intervals for maintenance?

My current thoughts are:

• Engine oil: ~500 track miles
• Tranny flush: Every season
• Differential flush: Every season
• Will probably move to water wetter & water
• Thinking Wheel bearings every 3 seasons
• things I am missing????

[Fabb]

If you want to do a square 275 conversion, you'd need a small 'BBK' to fit 18 inch wheels. Many uses Essex AP racing brakes 9660/9668 kits. On top of that, you will need more than -3.0 degree of camber at the front and -2.5 at the back. That means camber plates, coilovers, rear camber arms and toe links. Some can get away with rear toe links only but I recommend camber arm to pull the rear wheel in, in case the slick rubs.

[DRLane]

Originally Posted by Fabb

If you want to do a square 275 conversion, you'd need a small 'BBK' to fit 18 inch wheels. Many uses Essex AP racing brakes 9660/9668 kits. On top of that, you will need more than -3.0 degree of camber at the front and -2.5 at the back. That means camber plates, coilovers, rear camber arms and toe links. Some can get away with rear toe links only but I recommend camber arm to pull the rear wheel in, in case the slick rubs.

Have a buddy running square 305 DH on 10.5 on his M2C. It's street car with MCS 3way and similar setup as M2CSR (regarding wheels, spacers, offsets). Lots of options to get much wider tires if desired.

[OG Shark]

Originally Posted by rbahr

Thanks for the feedback all.

CSBM5: I am now turning everything off, and I got ABS, rear diff, and steering coded - so better. I absolutely need more seat time in this thing, but I initially found the on center steering feel to be vague or numb. The GT3 LSD was 'improved' and running motorsports clutch disks.

DVAS: When figuring out what car I wanted, I was targeting sub 2:05 at WGI. With the M2 as it is I was seeing ~2:13 recently. I had considered the Corvette, but as a buddy said 'It is a digital car trying to look analogue', and having instructed in a number of them, it really didn't do it for me.

OGSHARK: absolutely correct - " The M2 is more of a street car that can track while the GT is more of a track car that can street.". I will read through your build to see what you did.

All: I need to remember that I made a choice to no longer wrench on my car for 2-3 hours for every hour driven. I am also needing to avoid a crazy slippery slope, but I still need to tighten up the steering and shifting, and GET MORE SEAT TIME!

I will be going to a square setup for rims and tires, so that will change a lot of things, and I will need to figure out / dial in the shocks.

Does anyone have any recommended intervals for maintenance?

My current thoughts are:

• Engine oil: ~500 track miles
• Tranny flush: Every season
• Differential flush: Every season
• Will probably move to water wetter & water
• Thinking Wheel bearings every 3 seasons
• things I am missing????

In short to knock off the majority of the time I ran our custom spec single adjustable Nitron setup as the only suspension mod, Essex/AP Racing brakes all four corners (my home track is very hard on brakes - stock will not keep up at the pace it can run), Wagner intercooler, and Bend Calibration tuning with their flex fuel kit. With those being the focal points of the build the car was transformed and much, much quicker on track. That was actually the purpose of the car at that point - to show what can be done with the F87 with a few well thought out mods and still be an excellent daily driver.

Now since then we have definitely pushed the car a bit further. Running our custom 3-way Nitron setup, full SPL bits, Full Race turbos and still developing our aero package for the F87. Also working on a brake cooling package as we have achieved a pace that can even push the APs to their limit. And the car is only going to get faster as we start to finally get some cooler air down here in Texas. And once we finish building the motor and dct will be bumping the power some more. Still going to be a street car though - and still rides great on the street as is. This is definitely more extreme but our goal now is to see how far we can push this platform.

On the shifting I would strongly recommend the CAE shifter. It transforms the 6spd. You mention a half cage now that you are hitting 140+ - just keep in mind you still want to run the factory safety even with a half cage. Probably don’t need to tell you that since you have been in this game for a long time - but just want to throw it out there in case not. And it is good to see your concern for safety - definitely gets overlooked too often.

Originally Posted by DRLane

Have a buddy running square 305 DH on 10.5 on his M2C. It's street car with MCS 3way and similar setup as M2CSR (regarding wheels, spacers, offsets). Lots of options to get much wider tires if desired.

I run 305s all around too - best setup for this car. Have to run way too much camber in the front though - but dropping down in size and you can have a hard time with heat management with this heavy pig. I so want to get in to the fenders and massage them a bit - but I’m resisting so far since it is still a street car! I also just put carbon fiber fenders on soooo I won’t be chopping those up anytime soon.

[Fabb]

Originally Posted by OG Shark

In short to knock off the majority of the time I ran our custom spec single adjustable Nitron setup as the only suspension mod, Essex/AP Racing brakes all four corners (my home track is very hard on brakes - stock will not keep up at the pace it can run), Wagner intercooler, and Bend Calibration tuning with their flex fuel kit. With those being the focal points of the build the car was transformed and much, much quicker on track. That was actually the purpose of the car at that point - to show what can be done with the F87 with a few well thought out mods and still be an excellent daily driver.

Now since then we have definitely pushed the car a bit further. Running our custom 3-way Nitron setup, full SPL bits, Full Race turbos and still developing our aero package for the F87. Also working on a brake cooling package as we have achieved a pace that can even push the APs to their limit. And the car is only going to get faster as we start to finally get some cooler air down here in Texas. And once we finish building the motor and dct will be bumping the power some more. Still going to be a street car though - and still rides great on the street as is. This is definitely more extreme but our goal now is to see how far we can push this platform.

On the shifting I would strongly recommend the CAE shifter. It transforms the 6spd. You mention a half cage now that you are hitting 140+ - just keep in mind you still want to run the factory safety even with a half cage. Probably don’t need to tell you that since you have been in this game for a long time - but just want to throw it out there in case not. And it is good to see your concern for safety - definitely gets overlooked too often.

I run 305s all around too - best setup for this car. Have to run way too much camber in the front though - but dropping down in size and you can have a hard time with heat management with this heavy pig. I so want to get in to the fenders and massage them a bit - but I’m resisting so far since it is still a street car! I also just put carbon fiber fenders on soooo I won’t be chopping those up anytime soon.

What's the wheel spec for 305 all around? I assume something 10.5 with large offset and you add 20mm some spacers to fit. Also I believe MCS has thinner shock body to give larger front wheel clearance. My ohlins are thick af haha

[OG Shark]

Originally Posted by Fabb

What's the wheel spec for 305 all around? I assume something 10.5 with large offset and you add 20mm some spacers to fit. Also I believe MCS has thinner shock body to give larger front wheel clearance. My ohlins are thick af haha

I run 11’s in the rear so my fronts are spec’d to fit a 10.5 without spacers. If you run one of the common 10.5 square setups something like an ET33 would work with 12mm spacers up front. I still have the stagger so I can run larger yoko slicks in the rear when its yoko time and not pirelli.

Yes the Ohlins are a bit on the larger side - the spring perches are really big. I myself run Nitron on my M2 and they have more clearance. We also spec the springs to be shorter to help bring the perch up some. MCS is a similar fitment to Nitron.

[rbahr]

Hi All,

Jason: The shocks are MCS 3 way, remotes. Currently running 600 / 700 lb springs - what BW suggested. I suspect that these are a bit on the lighter side.

Fabb: The 1st mod I did was to replace the front brakes with the Alcons - endurance pad setup (24mm). The rears are still stock. I had some GT3 ducting bits laying around, so I pulled the front backing plates off and jiggered up some ducts. Will do the same on the rears. Current alignment is:
Front:
Caster: -8.4 / -8.5
Camber: -3.2 / -3.2
Toe: .11 / .1
Rear:
Camber: -3
Toe: -.15 / -.16

I need to redo this and start with a good corner balance / ride height.

Has anyone ever looked at Bump on these cars?

WRT tires / rims - I have a set of 10" Apex rims SM-10, 18 x 10 ET33 with 12mm front spacers (5mm spacers MAY work, but this was the safe way). I was targeting 275's but sounds like I can go a bit bigger. I did manage to get brake templates for the front Alcon caliper, and these rims will work fine - passed this along to Tom @ Apex. BTW th

Jason: 305's are a bit large for 10.5" rims - I ran 305's on the Porsche with 12" rims - and that was a good combination - although the 12's could also handle 315's

I am going to stay away from modding the motor for now, I went that route with my STi, and that was a never ending source of heat problems. As it is, the car manages the heat well, my oil temps stay pretty low. Also I still have a warranty that I want to coddle for a bit.

I will look into the CAE shifter, I don't really need to speed up the shifting - adds stress to the synchros, but I really need to clean up the sloppiness. I and ordering up the CS Race motor mount inserts, that should help. I need to look at the tranny mounts and I might look into machining up some bits over the winter.

The rubber in the front end needs address, I was looking at the CS race parts - not sure who's bearings they use, Porsche Motorsports uses Hirschmann which I really like, just wish they were affordable. The rear also.

Ray

[Fabb]

Originally Posted by rbahr

Hi All,

Jason: The shocks are MCS 3 way, remotes. Currently running 600 / 700 lb springs - what BW suggested. I suspect that these are a bit on the lighter side.

Fabb: The 1st mod I did was to replace the front brakes with the Alcons - endurance pad setup (24mm). The rears are still stock. I had some GT3 ducting bits laying around, so I pulled the front backing plates off and jiggered up some ducts. Will do the same on the rears. Current alignment is:
Front:
Caster: -8.4 / -8.5
Camber: -3.2 / -3.2
Toe: .11 / .1
Rear:
Camber: -3
Toe: -.15 / -.16

I need to redo this and start with a good corner balance / ride height.

Has anyone ever looked at Bump on these cars?

WRT tires / rims - I have a set of 10" Apex rims SM-10, 18 x 10 ET33 with 12mm front spacers (5mm spacers MAY work, but this was the safe way). I was targeting 275's but sounds like I can go a bit bigger. I did manage to get brake templates for the front Alcon caliper, and these rims will work fine - passed this along to Tom @ Apex. BTW th

Jason: 305's are a bit large for 10.5" rims - I ran 305's on the Porsche with 12" rims - and that was a good combination - although the 12's could also handle 315's

I am going to stay away from modding the motor for now, I went that route with my STi, and that was a never ending source of heat problems. As it is, the car manages the heat well, my oil temps stay pretty low. Also I still have a warranty that I want to coddle for a bit.

I will look into the CAE shifter, I don't really need to speed up the shifting - adds stress to the synchros, but I really need to clean up the sloppiness. I and ordering up the CS Race motor mount inserts, that should help. I need to look at the tranny mounts and I might look into machining up some bits over the winter.

The rubber in the front end needs address, I was looking at the CS race parts - not sure who's bearings they use, Porsche Motorsports uses Hirschmann which I really like, just wish they were affordable. The rear also.

Ray

Sounds like you're off to a good start with the suspension modding. This platform also desperately needs a rear wing to put the power down, especially if you running square setup. M2csr wing is a really good option for moderate amount of downforce

[OG Shark]

Originally Posted by rbahr

Hi All,

Jason: The shocks are MCS 3 way, remotes. Currently running 600 / 700 lb springs - what BW suggested. I suspect that these are a bit on the lighter side.

Fabb: The 1st mod I did was to replace the front brakes with the Alcons - endurance pad setup (24mm). The rears are still stock. I had some GT3 ducting bits laying around, so I pulled the front backing plates off and jiggered up some ducts. Will do the same on the rears. Current alignment is:
Front:
Caster: -8.4 / -8.5
Camber: -3.2 / -3.2
Toe: .11 / .1
Rear:
Camber: -3
Toe: -.15 / -.16

I need to redo this and start with a good corner balance / ride height.

Has anyone ever looked at Bump on these cars?

WRT tires / rims - I have a set of 10" Apex rims SM-10, 18 x 10 ET33 with 12mm front spacers (5mm spacers MAY work, but this was the safe way). I was targeting 275's but sounds like I can go a bit bigger. I did manage to get brake templates for the front Alcon caliper, and these rims will work fine - passed this along to Tom @ Apex. BTW th

Jason: 305's are a bit large for 10.5" rims - I ran 305's on the Porsche with 12" rims - and that was a good combination - although the 12's could also handle 315's

I am going to stay away from modding the motor for now, I went that route with my STi, and that was a never ending source of heat problems. As it is, the car manages the heat well, my oil temps stay pretty low. Also I still have a warranty that I want to coddle for a bit.

I will look into the CAE shifter, I don't really need to speed up the shifting - adds stress to the synchros, but I really need to clean up the sloppiness. I and ordering up the CS Race motor mount inserts, that should help. I need to look at the tranny mounts and I might look into machining up some bits over the winter.

The rubber in the front end needs address, I was looking at the CS race parts - not sure who's bearings they use, Porsche Motorsports uses Hirschmann which I really like, just wish they were affordable. The rear also.

Ray

Can you verify the toe settings? Per what you wrote you are running front toe in and rear toe out? Springs - I run 700/800 with my Nitron setup. MCS & Nitron in my experience seem to like similar springs rates so maybe a little room to work there without getting overly harsh on the street. The guys at BW are really on point with this stuff - so maybe discuss with them since they know the valving you are running as well.

I agree on 10.5 not being optimum for 305s. Unfortunately part of the compromise with this platform as it performs better than dropping down in width. 10.5 is still within Pirellis spec for the 305 and we have run that combination in our racing as well with good results. Optimal? No - but it does work. When I run yoko slicks I run 280 in the front and 300 in the rear just fyi.

Understood on the motor - warranty is nice. I will say this platform does manage heat very well from the factory. You can eventually outrun it but it takes a good mix of hard track characteristics and driving to get there. Good thing about this platform is that it doesn't become a never ending chase for cooling as you add power. But like you said you start getting into warranty issues adding power - so understandably not time yet if you want to keep BMW on the hook for now. Couple of things down the line though - ethanol helps keep the engine from pulling timing as things get hotter. It does burn through that already small tank pretty quick but it does make a difference on hard runs. Also a good tuner is going to give you much improved driveability in their maps. My choice (Bend Calibration) makes sport plus actually useable on the track and not just a spiky mess of throttle. Just thoughts for down the line.

Shifter - the CAE will help clean up the slop and also is much more precise than the oem. Big benefit is the much lower chance of the money shift. Big overall improvement to the fun factor as well.

Rubber - my thoughts on this platform if you are going there already you might as well go all the way and swap arms. With bits like SPL you also get the benefit of geometry correction and stronger components as well as locking in the alignment a bit better. When you have already stepped up to a 3way damper system I feel like this is the next best step to finish off the suspension. And no issues running them on the street as well. I run 80A motor mounts & 95A trans mounts with no complaints on the street either. Do keep an eye on the rear axles - I had to move to the KMP diff bracket to help relieve the issues from lowering the car - already had signs of failure. This does introduce some whine into the cabin though - but I actually kind of like it. If you do just want to swap bushings there are a few out there - Turner has a good selection to help compare.

Not sure what you mean by looked at bump?

[rbahr]

Jason: I mean has anyone measured bump steer on these cars? Good advice on the suspension. With the M2 CS Racing motor mount parts - it looks like the motor mounts essentially become solid. In general, I am not really worried about NVH. WRT tuning, yep the factor setup is kinda a mess at part throttle...

Please reverse signs on the toe settings - I transcribed things poorly

Fabb: my experience with rear wings is that you also need to do the front of the car as well - splitters / dive planes... Would you agree?

Thanks for the inputs!

Ray

[OG Shark]

Originally Posted by rbahr

Jason: I mean has anyone measured bump steer on these cars? Good advice on the suspension. With the M2 CS Racing motor mount parts - it looks like the motor mounts essentially become solid. In general, I am not really worried about NVH. WRT tuning, yep the factor setup is kinda a mess at part throttle...

Please reverse signs on the toe settings - I transcribed things poorly

Fabb: my experience with rear wings is that you also need to do the front of the car as well - splitters / dive planes... Would you agree?

Thanks for the inputs!

Ray

I haven't seen anyone go so far as to measure it - stock, lowered or otherwise. I personally haven't seen signs of it in my car and have not heard much complaint from others on it.

Maybe clean up the front toe & try to even them out. Also found for me I like more toe out in the front (0.30 to 0.40 total). The rear I also like in that range in. Also the rear camber is a decent amount more than what you typically see run on this platform. 1.8 to 2.2 seems to be a good place if you feel like trying a bit lower.

A smaller wing like Fabb mentioned or the m240iR wing can definitely help settle the rear a bit in the high speed stuff. For me it is a trade off because it does need a bit of front to help balance it - so really kind of a pro/con for me with the good outweighing the bad by a bit. We are still working on our full size wing about ready to retest - we should be hitting close to 170mph on the back straight at COTA this fall and making sure we have eliminated all deflection. When paired with a proper track splitter it car is transformed - real aero is a huge boon on this car.