View Full Version : Master Cylinder questions, disc/drum, disc/disc. Pushrod?

01-21-2005, 01:34 PM
I've bought about 6 different MC for my car, non work. I have a SS brake conversion up front and that master developed a leak. I've gotten the wrong parts from them before, and don't want to deal with it as well as I'm swapping to the C5 system with power boost.

So, what I need to know is:

On most of the mc I've tried the pedel hits a hard stop. Like metal to metal, not firm from hydraulic pressure. Why? Wrong master or is the pushrod wrong?

How do you tell if the car came with power or manual brakes? It was a 4 wheel drum car, but had the A/C and custom interior and power steering. Will the id plate or VIN tell me?

If I get a disc/drum mc, will I have to change it again when I add rear discs? What about the booster?

Finally, will 10bolt discs work on a 12 bolt? I wondering if I should wait to upgrade the rear end before I get discs for the back.

Sorry for the long questions, but I'm really anxious to get this car going after 6 years and I'm confused about brakes.

01-22-2005, 09:03 AM
If the MC is not matched to calipers the volume of oil in the MC is not enough to move all pads full distance, so it goes full travel before pads hit the discs , also if you use MC for disc/ drum from disc/ disc or drum/ drum it will not work. Also on a non servo pedal its recomened to use 9to 1 on servo 7to1 ratio.ie hinge pin to push rod 1" distance from push rod to pedal 7".On the MC thats from a disc drum set up theres a washer or spacer in the MC that keeps pressure on the rear drum springs so if you use it on a disc disc set up it keeps the pads on the disc ,on the servo brake pad cover no is 393521 /non is 3921648 hope this is of help

01-22-2005, 04:46 PM
My pedel wasn't even getting halfway to the floor. Maybe that's it...

I'll have to dig more.