The Stovebolt Site Forums The Shop Area Driveline Brake power booster - use disc/disc on a drum/drum

I'm looking to replace my master cylinder and started looking at the brake power boosters on classic parts and am leaning in that direction. Question is can I use a disc/disc booster on a drum/drum setup? I'd like to convert over to disc/disc later and don't want to buy twice. Thanks

Hy New_Ton, yes you can use the disc/disc master cylinder in a drum/drum application IF you use a resisdual pressure valve for drum brake application (I think 15 p.si.)in each brake circuit. When you convert over to disc brakes you can remove the resisdual pressure valves, I would also add a compensating valve to the system when converting to disc brakes, hope that helps

The booster would likely be the same for both set ups.
It's the master cylinder that would be different. The disc/drum MC has a built in residual valve which is required for the drum system. However, many aftermarket suppliers provide a Corvette MC with all of their applications. In this case you will need a separate residual valve for the rear. They should be available through most suppliers of the other parts. You will probably find that it is unneccesary to change to 4 wheel discs, changing the fronts will be a vast improvement. I installed a dual diaphram booster and dual MC on a 55 one ton and the brakes were super. They have 12" drums but the main weakness is the cheesy stock master cylinder.
Fred