looking for a new booster

[johnrobbsmusic]

I have a 67 Barracuda Formula S w/power discs (4 piston)..My booster was bad (broken spring or something so when you pressed the brakes, it just pulled the pedal to the floor so I put a different used one I had lying around and it doesn't work either (probably bad valve inside? there's no assistance to the brakes whatsoever with it). I cannot find a booster in my father's parts store system anywhere or local parts stores so I was wondering if one from a 73and up power disc car would work w/a proportioning valve?

 

[BillGrissom]

Should work identical, if the same diameter booster. I assume you are re-using the original MC. The assist force is just the engine vacuum times the diaphragm area. The exact formula should be: Fboost = 0.491 Pvac * Aboost
where Pvac is the pressure below atmospheric "in Hg" and Aboost is "sq in". Check since writing this on the fly. Typical might be 16 inHg acting on 50 in^2 to give 314 lbf. If a double - diaphragm type, double the force.

There is a lot of leeway, since not all cars have the same manifold vacuum (wild cam, etc) and the boost needed is subjective. I put a booster from a 90's Breeze w/ alum MC on my drum-brake 65 Dart, and it works fine. I did have to rat-tail file the bracket holes slightly.

 

[OneOfMany]

Check out boosterdewey.com. He can refurbish/restore or sell parts for fixing.

Grant