I had power drum brakes on my yellow 74 Hornet. I used the discs from a 78 Concord with the drum brake master and booster that was already in the car. A disc brake master will not fit on a drum brake booster. On the pass side fender well near the starter is a monster of a proportioning valve on my Orange 74 which has factory power disc brakes. The 78 Concord had no proportioning valve and was non power. I plumbed a Villwood adjustable proportioning valve into the front brakes and set it in the middle fixing to adjust it if I needed to. But after 5 years I have still yet to touch it. Also if you use a drum brake master you have to remove the pressure valve from the master at the exit port of the master where the brake line for the discs comes out. Having a factory car with discs and a converted one to compare stopping power to I have this to say. My converted car stops just as good as the factory
car with one minor exception. It requires a slight bit more pedal pressure to stop than the factory car. The difference being that the booster for a drum brake car is a single diaphragm and the disc brake booster is a double diaphragm.
"Doc"
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