ok i have an 88 iroc. I have installed the 1LE front brake setup but my car is originally a disk/drum car. I want to convert the rear to disk. I'm changing to a fourth gen rear, i will be using that disk setup. Will I HAVE to change out my master cylinder, I know I have to change the proportioning valve or have it re-valved. will this proporting valve work for me? http://www.hawksthirdgenparts.com/82...nlypair-1.aspx It shows only for the 90-92 but i've seen the same part number for 82-92s on other distributors.

 

No, you have the correct master.
No, that proportioning valve will have the wrong thread pitch for your 88. Here's the one you need:

http://www.flynbye.com/catalog/i40.html

More info toward the bottom in the following link:

https://www.thirdgen.org/forums/tran...-10-bolts.html

JamesC