Is there any difference between drum and disk brake proportionong valve? I was told it is not a Valve just a device to split the fluid betwen the rear brakes

Drum brakes used a simple distribution block. Disc brakes used a combination valve with built in proportioning and metering (hold-off).

what system (73 duster I'm assuming) are you working with now & what part or parts are you considering adding/changing? More info please

When I changed from race to street, I took off the proportioning valve that was on the car and cleaned it. I had a shop do some work and told them to put it back on the car. They installed another valve and now my brakes are weird. When at MATS, I drove my friends 73 Duster for the weekend. The brakes were great. He told me that the car is a disk/drum brake car. I am trying to figure out why my brakes seem so poor. I have a DR DIFF MC. Something is wromng and I'm trying to figure out what is wrong. I put on new metalic pads but didn't surface the rotors. I will surface the rotors when I have money and change the block to the one that came off the car. I hope that will fix it.

disc/drums I'm assuming. Not enough braking is the complaint? what bore MC/what calipers. I'm assuming the rear drums are spooned up & there ain't no air in the system (they dont pump up)

Ted...My 73 Duster has a 1 1/32 inch piston bore...with the stock proportioning valve...

I removed the power brake booster and the brakes are manual with the newer 2 bolt master cylinder.

This is the car he is referring to.