on a similar question, I have installed a late model non-power dual piston master cylinder in my 54 chevy truck. I a told I need a proportioning valve, but no one can explain WHY. What i get is "the back brakes will lock up" which doesnt make sense to me.
In the original configuration, all four wheel cylinders were subjected to equal hyd. pressure from the single piston. as the dual pistons are of equal size, and traverse an equal distance when the pedal is depressed, there should be the same pressure at all four wheel cylinders. If weight dist. made the critical difference, than a proportioning valve would have been necessary with the original kit. Anyone?
