owners (and have driven two of the cars) making between 600-750 HP (E85 cars), and we are all able to get traction in second gear. They just make the car so much more fun! I have the 225/45/16s in the front, and the 245/45/16s on the rear, on stock wheels. The difference from front to rear diameter is about 1/2", not noticeable to me. It allows the car to handle really well.