That's interesting...I bought a new master cylinder prior to deciding on the rear disk kit. So I had it still in the box and went back to O'rielly's and asked if I needed a different M/C to go 4 wheel disk. Dude said I didn't...all I needed was the 4 wheel disk combo valve/distro block. He says he did the same with his '69. Does this sound kosher to you? He's been dead on with advice in the past.

 

disc brakes move a lot more fluid than drums, therefore they will have bigger bores in the master cylinders. if you use a master than isn't for complete disc brakes, there is always the possibility of your rear discs dragging.

also, is this a manual or power application, or was it always a power system?

 

Yes, it's a power system from the factory. 4 wheel disk wasn't an option in 77...not sure when 4 wheel disk became available. Do you know what year model master cylinder I'd be looking for? Will it mate up to my power booster?

 

there are plenty of companies out there that have masters for your application. you might have a bit of difficulty in your local parts store though because they aren't usually good unless it is a factory installed part. try any good mailorder warehouse. just look in any Hot Rod or Super Chevy and there are plenty of vendors

you will have no problem with it mating up to your booster

 

1969 SS> Just wanted to follow up. Appreciate the advice...it got me asking the right questions. I've posted the reply I got from Brakeman INC in regards to my master cylinder in case others have similar questions. Thanks again.


Hello Mike,
Sorry I'm just getting back to you now, we were at SEMA all last week. To answer your question, the new stock disc/drum master cylinder will work as long as you use the correct disc/disc prop valve. The actual bore size is the same for the two masters-there is just different reservoir capacity-so the pedal effort should be the same. So if you keep an eye on the fluid level for the rears, you will be fine. Remember to bench bleed the new master thoroughly before installing it; mount it on your bench [or somewhere off the car] and run lines from the two ports back into the reservoirs. Pump the master slowly several times to remove the air inside the master itself, then leave it full with the ports plugged and install it on the car. You will lose some fluid when you hook up the brake lines, but it will save you from chasing an air bubble around the system.
Once the master is connected, bleed the brakes on the car thoroughly starting with the furthest caliper [right rear] and moving in order to the nearest caliper [left front].
That should do it, feel free to contact us with any further questions you might have.

Best regards,
Cory Lamarra
The Brake Man, Inc.
838 Calle Plano
Camarillo, Ca. 93012
805-987-STOP (7867)
TheBrakeMan911@aol.com
www.TheBrakeMan.com