I put a disc brake rearend in my 87 camaro and the back brakes wont work. We looked in Yearone and its says it takes a different master cylinder for the disc brakes. Do I need a new master cylinder or do I just need a proportiong valve? Thanks

 

This post is a few weeks old, but I am pretty sure you can do one or the other. Either get a new prop. valve OR get a new master cylinder. I've also seen people keep both the original master cylinder AND original prop. valve and splice in an adjustable proportioning valve made by Wilwood. I have the adjustable prop. valve, but still need to put it in. I need to replace my brake booster first. Hope this is some insight for you and good luck.

 

You can use either master cylinder, it will only make a difference to pedal feel.

 

i just did the same swap into my camaro... nick, did you ever get your brakes to work? if so, how...my car is still in the driveway, but id rather not find out the hard way that the brakes dont work...

 

Seems to be a popular mod lately...

I just ordered a new MC with the disk prop valve assembly from GM Parts direct for 200 bucks. The difference is just the prop valve compared to what I have now powering my rear drums. Apeiron said it right. You can use either but having the one for disks will make a difference in pedal feel. I opted for the new master cylinder because I don't want crappy pedal response AND my MC is getting on in years. The pressure to the passenger side compared to the driver's side was worse leading to uneven braking.

Don't forget your different e-brake cable!