I am helping a friend with his 56 vintage racing Corvette. Here is the problem. It has been converted to disc/disc from the old drum brakes. Today I discovered that it has what appears to be a mc from a 67 Camaro/Chevelle on it. Couldn't turn the rear wheels by hand at all. If I opened a rear bleeder a very small amount of fluid would come out under just a little pressure, then they would turn, put the brakes on then no turn. It is hooked up with the front of the MC to 4 piston calipers with 2 pins and rear to rear 4 piston calipers with 1 pin holding the pads. I assume there is a residual pressure valve in the rear of the MC. I can't find any in line going to the rear. I know we could probably get a disc/disc manual MC for a 68 Corvette but he would like to take the car out this weekend. Is it possible to remove the residual pressure valve if it is inside the MC? Let me know GL

Yes, it does sound like a residual pressure valve inside the MC. And yes, you can remove them from the ports of the MC by taking them out where the lines screw into it. This, of course, means opening the system and then having to bleed them again, so why not swap to a different MC and save some work? If this is really the drum/drum MC and you are trying to hook up some late model PBR style calipers... then good luck! You will find you will have a very stiff pedal! You should consider going to a MANUAL disk/disk MC and even then, you might still have trouble getting them to stop as the later model PBR's take a lot more pressure to stop.

Good luck,
Bill C.