the actual suspension. I felt a difference in that the rear of the car felt "tighter" or "stiffer", but others have reported no noticeable difference. I have also had people saying they did not feel a difference with Carbing strut tower bars so... *shrug* To me the Z32 is a heavy car and not stiff enough for its weight, it flexes too much... anything that stiffens up the chassis is something I plan to do. Up next is the front fender brace...