Originally Posted by Hotrodz

You don't have to be traveling at a 100 mph to have understeer. Understeer is when you turn the wheel and the car continues to go straight and adding addition input or turning does not help in getting the car to turn. I NASCAR they call it push because car wants to push through the turn. So Rusty's comment that you aren't driving hard enough refers to how aggressively you take a turn and that can be at 15 mph. It is about your inputs, speed into the corner and power out of said corner. So with your tire combination and the weight of the front end of the Z it is going to understeer when driven hard or at the limit for your tire and alignment setup.