I've read a bunch of threads and am getting a little wacked out. I've got a '88iroc with the shitty rear calipers. I've located a 89pontiac rear w/ the PBR calipers, back plates, hoses and lines. So heres my questions: Are shims going to be needed to mount the calipers and plates? Is there a different master cylinder available to firm up and shorten the pedal travel? I know I have to change the handbrake cable, anything to watchout for? I realize you guys are way past this with the C5 and LS1 upgrades but till I can go that route this will help me a bunch, Joe

 

Why not simply swap the entire PBR rear end into your car (and save yanking the axels and so on)?

I used shims to help center the caliper over the rotor. Other members may say that since the caliper floats anyway, the shim(s) aren't necessary, but shims did come from the factory on 10-bolts. The J50 drum master is one you need. More info in the following link:

https://www.thirdgen.org/forums/faq-...iscs-89-a.html

JamesC

 

thanks James, the parts are coming from an axle that's fairly high mileage and 3 states away. My car is low mileage (26K) so I know it's all like new on the inside. The J50 disc/drum master you mention, is that to firm up the pedal? Do I change the proportion valve too? I guess it's back to reading those threads again!

 

Here's a thread with appropriate part numbers for both the master and prop valve:

https://www.thirdgen.org/forums/brak...t&pagenumber=3

Here's another on pedal effort:

https://www.thirdgen.org/forums/susp...fferences.html

Also, check the following link for upgrading rear brakes:

http://web.archive.org/web/200605221.../1LEbrake.html

JamesC

 

THANKS!! Fine bunch of people here!!