What is this?
Cars with front disc brakes use a proportioning valve. 4 wheel drum cars used a distribution block. They are not the same thing.
Distribution blocks look like this:
Proportioning valves look like this:
The proportioning valve for disc/drum systems has a few functions.
It is designed to reduce pressure to the rear brakes since the rear brakes don't need the same amount of pressure as the front needs.
Disc calipers need more volume and pressure than the wheel cylinders in the rear drum brakes.
Cars with front disc brakes use a proportioning valve. 4 wheel drum cars used a distribution block. They are not the same thing.
Distribution blocks look like this:
Proportioning valves look like this:
The proportioning valve for disc/drum systems has a few functions.
It is designed to reduce pressure to the rear brakes since the rear brakes don't need the same amount of pressure as the front needs.
Disc calipers need more volume and pressure than the wheel cylinders in the rear drum brakes.