Proportioning Valve?

The brass block is really a distribution block. The proportioning is done with wheel cylinder / caliper piston sizing. When I do a conversion I use the distribution block from the disc car just because I have it but one time used the drum distribution block to see and the brakes worked fine and the braking bias seemed "normal".

Proportioning valves actually limit pressure to the back brakes to keep the bias towards the front. When you get your conversion done take it out and do a hard stop. If the back brakes lock up before the front then you will need a proportioning valve.

I really wonder if they are indeed the same. If someone had an old parts book they could see if they were the same part number.


Chuck