Beware of using polyurathane bushings on any car intended for street use. I totally wrecked the ride quality and pleasure of driving my 87 IROC using these bushings thinking if I did I would have great performance and would never have to replace a bushing again.. Boy was I wrong. The cons far out weigh the pros. I found using these bushings in the front a-arms and rear control arms alone made the ride so harsh it felt like I was gonna lose the fillings in my teeth, but all that is nothing next to the squeaks and noises they make. The bushings make the car sound like a sloppy jalopy going down the road not to mention the fact that people will turn to look at the piece of crap that just pulled into the parking lot they heard coming a block away. These bushings certainly have there place and work excellent when used with the sway bars,torque arm clam shell mount, and panhard rod. They do help to improve traction when used in rear control arms and I have kept mine in the tubular arms I'm using back there because I am willing to live with the slight harshness they create, but having them in the front arms is unbearable. The squeaking alone will drive you insane and don't think the lube they give to use is the answer because it hardly does anything and lasts about a day. You are far better off and will have better handling performance using koni shocks, frame connectors and a strut brace in attempt to stiffing the car that way rather than attempt to eliminate the minor amount of bushing deflection that occurs during hard cornering with stock rubber bushings. Also think hard before using the poly transmission mount also unless you don't mind the drivetrain vibration that will result. The poly torque arm mount worked great on my car and eliminated some unpleasant noises from the arm banging around when shifting from drive to reverse and such, but using the poly main trans mount made the car vibrate wicked at slow speeds, a condition that wasn't there with the factory rubber trans. mount. The main draw back I have found with the poly bushings is, that they transmit noise and vibration almost as bad as a solid mount. I have owned many different GM cars and trucks and attempted the use of poly bushings many times with mixed results. All my other cars had full frames and certainly seemed to be more forgiving to the use of poly bushings especially in the drivetrain. It wasn't until I bought my 3rd Gen Camaro that I fully experienced the full scope of the problems that arise using the poly control arm bushings and trans. mount on the street in a uni body design.