What tires are you running? I've learned that if you have M grips up front, they tend to expand after a while. This leads to a roll in high speed turns. A couple of guys told me to try different tires, I have "A's" in the front and "S's" in the rear. I'm thinking of trying S's in the front also just to see what it's like. I was stumped for months trying to figure this out. The car works great now.