I am in the process of switching over to a set of 4th gen calipers. See this thread: http://www.camaros.net/forums/showthread.php?t=57243&highlight=4th+gen+rotors

Anyway, my update is that I have purchased '98 Camaro caliper brackets (no integral parking brake), the abutments, and will be making my own caliper brackets. My questions are, what is the thickness of the '98 Camaro rear rotors?

I currently have '79 Pontiac Trans Am rotors on the back of the car, and if possible I would like to retain them with the new calipers if possible. What are the thicknesses of the two rotors, and the diameter of each respectively?

I "believe" that the rotors for the T/A are larger in diameter. But, I also know that the swept area is wider-and likely most of the rotor face (swept area) would not be touched by these small calipers/pads. Regardless, I understand that the further out the pads contact the rotor the greater the stopping force that can be applied. With that in mind, if the T/A rotors are larger in diameter, I would like to see if I can make them work. Otherwise, if this is too much of a hassle, I can just purchase new 4th gen rear rotors and be done with it.

Any help would be greatly appreciated.

I don't know the answer (I rarely deal with 4th gen brakes, mostly Wilwoods), but I'm sure you can go down to your parts store and find out if nobody can help you out.

Well I think I have an answer on the rotor thickness. According to the O'Reilly auto parts web page the minimum acceptable thickness for use is .980" for both rotors-which means they should start out at approximately the same thickness.

Further research shows that the '98+ Camaros have 12" rotors on the rear. I guess I will be looking for a set of 4th gen rotors at this point as they are larger in diameter than what I currently have, and have a smaller swept area which better matches my caliper/pad arrangement.