TANKERG

I know I'm resurrecting the thread, and I skimmed through and I might have missed it, but if anyone is experiencing some squirrelliness under braking at a track, one of the first things to consider is, it might be you! I have had this problem and it is the slightest movement in the steering wheel while bracing yourself that causes the back end to move about (as long as you have a good alignment.)

So what to do? Basically, barely hold onto the wheel. Get rid of the death grip and hover your hands over the wheel where they are barely touching, and the speed wobbles go away. My coach told me while riding in the car to completely let go of the wheel while straightline braking at 128 MPH, and I said "hell no," so we compromised and I had one finger on the wheel, and the car tracked straight. He told me to do that for the one time only, that is not a practice to be done everytime, but I open my fingers and barely hold onto the wheel.

RotaryZZ

I can tell you that's not the case in my situation. I have driven a bimmer down the same straight before at about the same speed without any issue whatsoever. I honestly think it has to do with the set up of the rear suspension on the 8.

04Green

iTrader: (1)

I had a similar problem, chased it then noticed that with the stability control off, the problem does not appear. Can make it come back with stability on. I never hear it activate, but it probably does not take much.

elysium19

iTrader: (1)

M own experience - I tracke dthe car twice when it was entirely stock. And then about 5 more track days after I did some modest suspension changes. I had some similar (but I dont think quite as severe) issues under hard braking.

New setup - Tokico D-spec shocks and Racing Beat springs (the RB springs are probably the most 'mild' increase in spring rate you can buy for the 8)
I also added prgress tech sway bars, but I dont think that should affect this issue too much)

Now, braking is AMAZING. firmly planted, tested up to about 125mph hard braking.

At those high speeds, I think the simple fact that the stock suspension is meant for typical sporty driving, not track driving. It's not a fault per se, it's just not the intended use. But overall i think the nature of the stock suspension is a more likely culprit than any alignment issues.