The Stovebolt Site Forums The Shop Area The HiPo Shop Disc brake conversion question

Well i'm hoping i'm not beating this topic to death...my apologies if i am.

I've got a 52 chevy 1/2 ton. looking into front disc conversions..."Brothers trucks" sells a conversion with everything i need minus a new master. do i need a new master or is this not necessary?? Also since i'm here, for those of you who have completed a conversion, does anyone have a recommendation for who i should purchase a conversion kit from?? All input is appreciated! Thanks guys!

You will need a new master cylinder. I'd recommend buying a kit for that too. Go with the power booster also.

I put power disc brakes on the front of my '54 Suburban. I love the way it stops. I used the Performance Online kit for it.

I have also installed a CPP kit on another '54. Neither kit is a bolt in. You will have to do some mods. I had to cut and re-weld both MC brackets to get them where I liked it.

You can read about it here, about halfway down the page.

I got mine from performanceonline.com Very complete and easy to install.$649

I have installed numerous disc brake kits from ABS in Orange, CA. Truck shop, Brothers, CPP and numerous others in So Cal also sell kits. The system will not work with the original MC. I also recommend a power booster.
Fred

I installed a disc brake conversion on my '53. It worked just fine. A direct bolt on. I did not use a booster with it. I did install a corvette dual master cylinder though. You do want to have a dual cylinder so you can run the front and rear brakes on separate lines. Good for safety.

Dan

Dan, I read about your disc conversion. I'm doing my '52 now.First off did you install new fluid lines or use adapters for the new calipers? Did you use a proportioning valve. I have disc front,drum rear. Will any 2 portal master work if it's gm?? Thanks in advance!!

There is a science in master cylinder sizing, so no, not just anyone will do. The companies that sell brake kits ask a lot of questions, or they should, about the pedal type and ratio. They also need to know which caliper and what rear cylinder you are using.

Big bore cylinders apply more fluid at a lower pressure, so they take more effort.
Small bore cylinders apply more pressure but less fluid, so they take more pedal travel.

Ask the seller of the kit, they should know which one works with there system. Measure your brake pedal from the center of the pad straight down to the pivot pin, then from the pin to the point where the master cylinder rod meets it. Do a little math and you will have the pedal ratio.

Joe

When I did mine I bought a kit based on mid-70's midsize GM parts. My rear axle came from a '73 Chevelle (wagon) so I bought rotors, calipers and master cylinder for a '73 Chevelle and used the multivalve from the same car.

I had first determined that the Chevelle and my truck weighed close to the same and had similar weight distribution. My thinking was that I was letting the factory engineers figure out details like master cylinder size and proportioning valve.

I'm still driving it eight years later so I think the approach worked.

12181955

As I remember, I did not run totally new lines. I adapted the old lines to the corvette master cylinder. The folks that sold me the disc kit for the front also sold the porportioning valves as I kept the drums on the 1970 F100 rear axle. The company I bought everything from was in Washington State above Seattle but they're out of business. I'm certain folks like Classic Performance Parts in Southern California would have what you need.

Dan

So with the stock 3sp trans(possibly 700r4 havent decided yet if im going to do the converion or not) what booster set up will ineed or who brakets should i buy

If anyone has experience with these conversion kits, please PM me. I have major issues. Need some brain power asap!

Danhami, where in California are you? I'm in Sonoma County Nor. Cal. and there is a brake parts supplier here who can still get asbestos friction. Converting from "organic" to asbestos is like adding a power booster without the drum/rotor eating effects of metalic friction.

I have also found asbestos pads for GM "metric" calipers on ebay. So the "metric" calipers are an option to consider. There is even a rear brake version of those that has an e-brake.

I live in south san Francisco. I already have the front disc conversion. I'm running into problems with the booster set up. Very irritated right now. Lol....I'm debating trying the firewall mount booster kit as opposed to mounting in the factory location....

On mine, I went with the under-floor power brake booster that I got from Speedway Motors. Everything works fine.

But if you're doing a disc conversion on your front, but keeping the drums in the back, keep in mind that you will need a manual proportioning valve.