[dvas]

Originally Posted by SEAT TIME RULES

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

I agree that linear springs are more suited for track duty than progressive. Having said that, the Bilstein PSS10s are engineered for dual duty, probably more street than track, and they came with progressive springs. Bilstein's clubsport variant is more focused on track only. Anyway's good for 0,59's at Lime Rock on street tires, so still a pretty great setup if not ideal.

[slap]

Originally Posted by M2C AW

+1

+2

[Talx]

Originally Posted by Karmic Man

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.

Interesting I have had this same problem with my setup at slow corners on the track, 40-45 mph corner where I would try and throttle threw the corner the car would under steer badly and drag the front tires, if I tried to get harder on the throttle the car would immediately over steer we and loose the rear end.to solve this I had to brake hard into the corner and only get back to throttle on the exit to stop this.

[ksalih]

iBrakeLate any updates?

[nando_514]

Originally Posted by Karmic Man

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.

Maybe I’m missing something, but if you read what you posted, the answer is all there.. Think about the chassis dynamically, what’s it doing when you roll on throttle? The rear end is squatting, and you’re picking up the nose (taking weight OFF the front-end). Again, maybe it’s just me, but when the nose of the car is lifting, wouldnt you expect understeer at that point?

You then point out that trail braking (using proper technique) seems to alleviate the issue. To me, it sounds like you’re overdriving the car. You may be operating at 105%, try dialing it back to 99% and LEARN FROM YOUR SLOWER SELF. I mean that in no disrespectful way, but there’s alot to be learned from your slower self.

[richard in NC]

The M2C understeers less than most cars I've driven on track, mostly 5 series.
But yes, at steady state throttle and large steering angle it can understeer a bit but technique can solve it.

One, use MDM mode and apply more throttle to rotate the car, but better yet, adjust your line to a later apex in and through the corner, and open the steering wheel sooner on exit. This reduces the slip angle, allows more front grip, and more rear acceleration.

I also recommend some time on a skid pad to learn the fine amounts of throttle between understeer and oversteer. The M2C can induce oversteer with a gradual increase in throttle, and doesn't need big stabs at it.

EDIT: I added a crude drawing to illustrate my point. Also note the later turn-in. Adjusting that by 2 feet makes a surprising difference!

[n8dgr84]

stock springs are too soft and alignment sucks
get an aggressive alignment with camber correction hubs, lower stiffer springs, and/or camber plates and you'll solve 90% of this issue.

[DRLane]

Originally Posted by richard in NC

The M2C understeers less than most cars I've driven on track, mostly 5 series.
But yes, at steady state throttle and large steering angle it can understeer a bit but technique can solve it.

One, use MDM mode and apply more throttle to rotate the car, but better yet, adjust your line to a later apex in and through the corner, and open the steering wheel sooner on exit. This reduces the slip angle, allows more front grip, and more rear acceleration.

I also recommend some time on a skid pad to learn the fine amounts of throttle between understeer and oversteer. The M2C can induce oversteer with a gradual increase in throttle, and doesn't need big stabs at it.

EDIT: I added a crude drawing to illustrate my point. Also note the later turn-in. Adjusting that by 2 feet makes a surprising difference!

Hmmm… Turn in and early/late apex is too situational to suggest one is faster or slower. Sometimes sure, other time not at all. It's like suggesting smooth is fast, when fast often isn't smooth.

Angle of your car at apex is more of the determining factor to throttle applications than early or late.

[theblackdawnr3]

Just ran my first autocross with a stock M2c and had this issue. Upon first impression, I was sure that this was an Active M differential tuning issue. The rear was stable while trail breaking through a corner but IMMEDIATELY let go as soon as I applied the smallest bit of throttle, which doesn't make sense dynamically as transferring weight to the rear should increase grip not lessen it. If I can't find a way to tune the locking, I'll be forced in to a setup with soft rear springs and more staggered tires than I would like.

[Wolfman’s Brother]

Originally Posted by SEAT TIME RULES

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

Can you speak to the change in dynamics the TC Kline setup made vs stock?

I’ve been advised to get more seat time (it rules) on the stock setup and alignment before progressing to the TCK setup and Cup2s.

[OG Shark]

Originally Posted by Wolfman’s Brother

Can you speak to the change in dynamics the TC Kline setup made vs stock?

I’ve been advised to get more seat time (it rules) on the stock setup and alignment before progressing to the TCK setup and Cup2s.

Don’t make the car faster until you are faster than the car - I like what you are doing there continuing to get seat time with the stock suspension.

Curious why are you targeting Cup2’s as part of the next step when you do upgrade?

[Wolfman’s Brother]

Originally Posted by OG Shark

Don’t make the car faster until you are faster than the car - I like what you are doing there continuing to get seat time with the stock suspension.

Curious why are you targeting Cup2’s as part of the next step when you do upgrade?

I need to just start a build thread instead of whoring everyone else’s threads but until then…

Because I’m sticking with 19s and I want something I can put some street miles on and it’s still my daily. Came up on the TCK setup from an instructor that had the M2C TCK dev car and couldn’t pass it up. Just out chasing zen, not records.

When I have a 991 to daily, the M2 can get more focused.

[OG Shark]

Originally Posted by Wolfman’s Brother

I need to just start a build thread instead of whoring everyone else’s threads but until then…

Because I’m sticking with 19s and I want something I can put some street miles on and it’s still my daily. Came up on the TCK setup from an instructor that had the M2C TCK dev car and couldn’t pass it up. Just out chasing zen, not records.

When I have a 991 to daily, the M2 can get more focused.

Ah ok, just went down that rabbit hole too for 19's on my E90. Was hoping one of the cheater 200s would would (preferably the yoko) but 19s are just rough to fit right now. Hear nothing but good things about TCK - definitely ought to be happy with it. Hear you on chasing zen - if you don't step out of these cars with a smile on your face every time you're probably doing something wrong. Hard to beat in fun factor.

[Harpinc]

Looks like push/kick to me.. Did you add more steering input very late right before apex and held that longer that you should've. The car looked to push... then the fronts gripped up and the rear came around..