Ok, trying to get my 87 4 lug into a 5 lug, 4 piston caliper setup for racing. I got the basics down, and found out all the master cylinders are the same unless you have abs between the years.
So my question is regarding the booster and stock proportioning valve. I will install an adjustable proportioning valve later, but just want to get some seat time first. Is the valve the same for the standard brakes or do I need to get one from a Turbo/4 piston caliper setup. Same question about the booster? I have heard they are bigger(Have a bigger resevoir). I tried to search the net and old posts but could not find any info on these two questions.

Thanks for the help!

 

if master cylinders are the same the size the booster will not make any difference. may only affect pedal effort, but I believe they are all the same. proportioning valve is likely the same from model to model since all second gens had 4 wheel disc brakes. if you were adding discs to the rear of a car that came with drums then you might have a problem. proportioning valve regulates the amount of force applied to the rear calipers. most street cars are setup with very little rear bias so you should be fine. if you find you need more rear brake then add the adjustable unit.