Here's my two cents on the master cylinder issue. I have an '83 K5 with the 6.2 diesel and hydro boost. I have had several hydro boost trucks and wouldn't go any other way. I swapped in an 8 lug 10 bolt front. It has 3/4 ton calipers on it which I believe have a 3 5/32" piston. Out back I have a 14 bff with Ruff Stuff disc brake brackets and 1/2 ton calipers which I believe have a 2 15/16" piston. I was trying to give the rear a little less braking force by going with a smaller piston caliper out back. They worked with my stock mc but I had only test drove it around the block a little. I did not want to have issues with the factory residual pressure valve or the lack of fluid flow to the rear using a disc/drum mc and proportioning valve. I wanted my brakes to be the best I could possibly make them. I like a stiff pedal feel also. I swapped in a disc/disc mc from a 1983 Chevy P30 1 ton step van with a 6.2L diesel and hydro boost brakes.
Here's the one I used. I prefer new over reman. I have had bad luck with the quality of reman parts in my career as a mechanic.
Here's the factory one for comparison.
It has the same port sizes as factory and a slightly larger piston size. The factory mc on my Blazer is 30 mm and the one I used has a 34 mm piston which moves more fluid and gives me a stiffer pedal and its also made for rear discs. I then swapped out my factory proportioning valve for a Summit Racing disc/disc one.
I test drove after a what seemed like a ton of brake bleeding. It has a good stiff pedal and will lock up my 35s no problem on asphalt and stop on a dime. My rear brakes do lock up before my front ones though so the rear end wants to come around on me. I will be adding a manually adjustable proportioning valve to the rear circuit to turn them down a little so the front will lock up first for better control. This is just how I ended doing my brakes. I will have to see how they continue to work in the future. I need to finish up some other stuff then I will be daily driving my K5 about 20 miles a day.
Here's the one I used. I prefer new over reman. I have had bad luck with the quality of reman parts in my career as a mechanic.
Here's the factory one for comparison.
It has the same port sizes as factory and a slightly larger piston size. The factory mc on my Blazer is 30 mm and the one I used has a 34 mm piston which moves more fluid and gives me a stiffer pedal and its also made for rear discs. I then swapped out my factory proportioning valve for a Summit Racing disc/disc one.
I test drove after a what seemed like a ton of brake bleeding. It has a good stiff pedal and will lock up my 35s no problem on asphalt and stop on a dime. My rear brakes do lock up before my front ones though so the rear end wants to come around on me. I will be adding a manually adjustable proportioning valve to the rear circuit to turn them down a little so the front will lock up first for better control. This is just how I ended doing my brakes. I will have to see how they continue to work in the future. I need to finish up some other stuff then I will be daily driving my K5 about 20 miles a day.
