[richard in NC]

Subscribed to this thread. I don't have an Olins setup but pure stock so far. I did experience the corner exit oversteer in a high speed sweeper at the Performance Center which seemed different than the typical "kick the back end out with throttle" oversteer. About 22 seconds into this video. https://vimeo.com/453262529

PS: On a skid pad a few months later, I did play with oversteer caused by gradual throttle and speed increase. The back end just starts an easy to control drift.... That could be just an M2C characteristic, possibly exacerbated by stiffer springs??

[pal]

Originally Posted by K-Fab

Present setup:
9.5 & 10.5 x 19 Apex EC-7 wheels
Toyo R888R sneakers - 265 & 295 running 36-37 hot
Ölins R&T suspension both front and rear are 10 clicks out (will play with these next round)
Car is set at 3 degrees camber, zero toe front
1.9 camber, presently mentally blank on toe in - 1 degree, I believe.

Manners are fantastic right up to starting to add throttle after apex and the back end gets twitchy, often leading to nice high speed drifting (can be fun, can make one's butt pucker).

It's quite consistent left or right handers and as the OP stated, the faster, more open sweepers seem to be more problematic than the tighter stuff

I'd done 4 track days in the M2 this year (stock suspension, 255/275 Good Year Eagle Supercar3 tires on 513Ms, Pagid RS29, DSC Off). While I am still getting used to the car, I definitely experience the rear end "drifting" out as you start to apply throttle past the apex. Having tracked a Z4M Coupe for 6 years many years ago, this behavior is not much different though it does seem a bit more exaggerated on the M2. BMWs in general exhibit slip angle when tracking out as you roll into the throttle and I've always tried to find the limit where slip angle becomes a drift or a tank slapper and try to stay there as must as possible.

My thinking is that the turbo torque makes this more apparent on the M2/M2C, throwing in the stiff rear setup of Ohlins accentuates it, and if you're tuned that takes it a step further. I believe you can play with spring rates and alignment to "tune" it to a level that works, but at the end of the day you are dealing with physics - 2 wheel drive, lots of power, lots of low end torque and 3450-3600+ lb cars.

[K-Fab]

@pal - I do believe you're on to something with those comments. Two of my buddies at the track run the Z4 Roadsters (completely set up as track cars) and they were both teasing me about "Get used to the loose rear, especially after 17 years of cheating and driving Audis with Quattro."

[bentom2]

Originally Posted by K-Fab

@pal - I do believe you're on to something with those comments. Two of my buddies at the track run the Z4 Roadsters (completely set up as track cars) and they were both teasing me about "Get used to the loose rear, especially after 17 years of cheating and driving Audis with Quattro."

@pal is familiar with that form of cheating.

[pal]

Originally Posted by bentom2

@pal is familiar with that form of cheating.

Indeed, I am. The last 5 years and 80-100 track days have been in a track prepped Audi TT RS Starting to get back in the groove of a RWD car again ...

[m2cWW]

Originally Posted by iBrakeLate

So I finally got the M2 Competition out on track after the mods, and I am having issues with the vehicle mid-corner to corner exit behavior.

The car has the Ohlins R&T with the Ohlins recommended spring rates, Ground Control Camber plates, 265/295 Yokohama A052 tires.

The front has 0 toe, rear has total 1/8th toe in. -3 camber front, -2.1 camber rear (drivers side), -2.7 camber front, -1.7 rear (passenger side). The track I visit most often is mostly all right hand turns, hence the setup being as this. Front rebound is set at 7 clicks, rear at 12 clicks (was originally 7 at rear but softened the rebound after)

The rear of the car starts letting loose from mid corner to corner exit on right hand turns. It is more prevalent on longer sweeping corners.

I am a pretty seasoned driver, and it does the above mentioned over steer with no jerking of the wheel, or rough application of power. In fact if you hold throttle steady and keep the steering angle steady the back ends up coming around.

All nannies are off, so its not a matter of the electronics throwing the car off either.

I was out on track on Wednesday, and back again yesterday (Sunday). On Sunday we took cross temps on tires and the rear can use more camber, front wasn't so bad.

I thought with the amount of stagger running with the tires the car would actually understeer from mid-corner to corner exit, however I can't even apply any power since there is way too much yaw.

I would appreciate anyone who has experience with the F87 chassis to chime in.

Hey man! I had the same issue on a different spring rate, but I set the rear toe to be .1 on both rear tires and camber to -2.4 (camber wasn't the issue, just a reference point for you) with 0 toe up front and -3.2 camber. I'm running into initial turn in problems now (under steer) but I'm going to play with my front damping to tune that out and hope the existing suspension settings will handle that well.

Just another data point for your reference, hope it helps in some small way!

[n8dgr84]

Love this thread.
Thanks for sharing the videos and troubleshooting process!

[chief1richard]

Originally Posted by K-Fab

Subscribed!

I'd swear that video was out of my cockpit. I have EXACTLY the same issue.

I got my car out this weekend (Inde Motorsports Ranch in Willcox, AZ - new pavement, FUN track) for the first time since getting all the suspension installed and set up.

Present setup:
9.5 & 10.5 x 19 Apex EC-7 wheels
Toyo R888R sneakers - 265 & 295 running 36-37 hot
RSR cage
Pagid Yellows (this is changing next round)
Ground Control camber plates (noisy things) and Turner adjustable rear toe arms
Ölins R&T suspension both front and rear are 10 clicks out (will play with these next round)
Ride height is 8 mm lower than stock (supposed to be 10mm lower). There was an intentional reason for the higher setting that's been addressed (trailer setup).
Car is set at 3 degrees camber, zero toe front
1.9 camber, presently mentally blank on toe in - 1 degree, I believe.

Manners are fantastic right up to starting to add throttle after apex and the back end gets twitchy, often leading to nice high speed drifting (can be fun, can make one's butt pucker).

It's quite consistent left or right handers and as the OP stated, the faster, more open sweepers seem to be more problematic than the tighter stuff.

I'll take the steps OP has as far as preload and ride height (I'm sitting too high - definitely in the rear) and see what happens next month at a smaller, tighter track (Wild Horse Pass - Bondurant course).

I really hope I can dial it in w/o going to a softer spring rate. I do agree that they seem to be pretty stiff the way Öhlins sets them up.

Other than this, the car is brilliant to drive on the track.

I am considering Ohlins BMS MR40 Coilovers and your car seems set up same as mine w/Apex 9.5, 10.5 EC7. Currently 255/35/18 (f), 285/30/18 (r). What Spring rate are you running? I do 6-10 Track days a year. Was leaning to 70 (f), 160 (r), as I understand 90 (f), 190 (r) can be a bit much for DD. Do you have any issues with 265/35/18 up front rubbing? BTW nice job noticing that poster had his Springs on the wrong ends.

[dvas]

For reference, the Bilstein B16 coilovers I'm running have 500lbs front and 800lbs rear springs.

I haven't run into any issues and oversteer/understeer can be dialed in/out with a few clicks.

[M2C AW]

I was experiencing a similar issue as OP this past weekend. I swapped out rear tires to a fresh set mid-day, and issue was gone.

[Gusman1]

Originally Posted by dvas

For reference, the Bilstein B16 coilovers I'm running have 500lbs front and 800lbs rear springs.

I haven't run into any issues and oversteer/understeer can be dialed in/out with a few clicks.

How many clicks F&R have worked for you?

[dvas]

Originally Posted by Gusman1

How many clicks F&R have worked for you?

I ended last season running at 6 clicks front/7 clicks rear on NT01s but was running 8 clicks front/7 clicks rear on RE71s. I look to run close but not at the hardest settings and adjust to dial out any understeer depending on tire model, tire wear, and conditions. I like a somewhat loose car and this seems to work well for me.

[Gusman1]

Originally Posted by dvas

I ended last season running at 6 clicks front/7 clicks rear on NT01s but was running 8 clicks front/7 clicks rear on RE71s. I look to run close but not at the hardest settings and adjust to dial out any understeer depending on tire model, tire wear, and conditions. I like a somewhat loose car and this seems to work well for me.

Thanks for the feedback. Just got mine installed but waiting on new tires then I'll start messing around with the settings.

[chiefsubjugator]

In general I feel like the back end of this car likes to swing out - isn't this kind of expected behavior of BMWs?

If I recall correctly, they talked about this in the savagegeese review - it's a fun trait but not as desirable for the track where you'd like to apply throttle as soon after the apex as possible.

Btw, I have little experience with other RWD platforms - do other RWD track cars tend to push (understeer) more when you apply throttle? I wouldn't trade my M2C for anything but I admit to sometimes wishing it had a little less oversteer when coming out of corners.

[dvas]

Originally Posted by chiefsubjugator

In general I feel like the back end of this car likes to swing out - isn't this kind of expected behavior of BMWs?

If I recall correctly, they talked about this in the savagegeese review - it's a fun trait but not as desirable for the track where you'd like to apply throttle as soon after the apex as possible.

Btw, I have little experience with other RWD platforms - do other RWD track cars tend to push (understeer) more when you apply throttle? I wouldn't trade my M2C for anything but I admit to sometimes wishing it had a little less oversteer when coming out of corners.

Depends how your M2 is setup. Most cars out of the factory are set up to understeer for safety reasons by the manufacturer. A few tweaks can remedy that quickly.

[chiefsubjugator]

Originally Posted by dvas

Depends how your M2 is setup. Most cars out of the factory are set up to understeer for safety reasons by the manufacturer. A few tweaks can remedy that quickly.

I'm fully stock right now running on PS4S. I'll have some more agressive rubber on the car once I burn these off though. Not planning many mods though maybe an alignment might be in order (I'm thinking a bit more camber in the back might help).

[Karmic Man]

Originally Posted by chiefsubjugator

In general I feel like the back end of this car likes to swing out - isn't this kind of expected behavior of BMWs?

If I recall correctly, they talked about this in the savagegeese review - it's a fun trait but not as desirable for the track where you'd like to apply throttle as soon after the apex as possible.

Btw, I have little experience with other RWD platforms - do other RWD track cars tend to push (understeer) more when you apply throttle? I wouldn't trade my M2C for anything but I admit to sometimes wishing it had a little less oversteer when coming out of corners.

There is no high torque RWD I have come across on track that understeers when throttling out of an apex...unless the front is absolutely shot from overheating...even FWD oversteers when using after market dampers and springs. During the initial turn in I found the M2C can understeer when throttling into a corner but not if one is trail braking. The M2C can understeer when sailing through a corner, that is not applying throttle at apex but always oversteers when one is throttling out of an apex. The only platform I know of that can understeer throttling at apex is rear engine 911s.

[ksalih]

OP, closely following this thread. Any updates?

[Rumbloki]

Originally Posted by Karmic Man

The only platform I know of that can understeer throttling at apex is rear engine 911s.

Isn't this also true of the RS3?

[Rumbloki]

Originally Posted by dvas

For reference, the Bilstein B16 coilovers I'm running have 500lbs front and 800lbs rear springs.

I haven't run into any issues and oversteer/understeer can be dialed in/out with a few clicks.

Are these conical coils?

[dvas]

Originally Posted by Rumbloki

Are these conical coils?

They are progressive, not linear. I presume I could switch to linear springs with a helper spring down the road but I'm not sure how much upside there would be. The suspension is pretty stiff while eating up bumps or wavy pavement much better than the oem suspension. I can seemingly hit curbs on track that others avoid.

[SEAT TIME RULES]

Originally Posted by dvas

They are progressive, not linear. I presume I could switch to linear springs with a helper spring down the road but I'm not sure how much upside there would be. The suspension is pretty stiff while eating up bumps or wavy pavement much better than the oem suspension. I can seemingly hit curbs on track that others avoid.

I run a linear 400/700 setup (TC Kline).

I've never been a fan of progressive springs for Auto X or track work.

For a car that's street driven on poor road surfaces they are the way to go, but remember they are a COMPROMISE.

My 400 lb fronts are fine with the Single Koni's on the street. 500 might be pushing it...

Just my .02