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Question on ports on master cylinder: Does it matter which line goes to which port? Front port for front brakes, rear port for rear brakes? Or does it not make any difference?

(Working on 1953 3/4 T. Chev. PU drum brakes--)

Thanks--T.K.

TK - no it doesn't matter, other than convienience of line routing: "when increasing the pressure at any point in a confined fluid, there is an equal increase at every other point in the container, i.e., any change in pressure applied at any point of the fluid is transmitted undiminished throughout the fluids.

Bill

Depends on what master cylinder you're using. If you have the Corvette style master cylinder, then np, it won't make a difference as that one was designed for 4 wheel disks with the same caliper on all 4 corners. But most disk/drum and even later 4 wheel disk masters will have specific front/rear porting. It's pretty much universal on modern vehicles (I have never seen any exeptions to this) for the port nearest the pushrod end of the MC to be for the front brakes, the other port for the rear.

There are three issues that I think of that make a difference.

First is the size of the bore. If both bores are the same size its a non-issue but if they happen to be different sizes you need to match them correctly to front and rear.

Second is reservoir size. Disk brakes require more fluid displacement and therefore usually require a larger reservoir. In a front disk/rear drum application that would make a difference.

Third is the possible presence of internal residual pressure valves. When needed disk brakes need a 2 pound valve and drum brakes need a 10 pound. If your master has built in residual valves they need to match your brakes.

While you describe your project as drum brakes if you are using a newer master it was probably designed for a disk/disk or disk/drum system and some of these issues could impact your project.