Do you have the factory belcrank that goes between the brake pedal and the booster? Trouble with those kits is they are a bag of mixed parts from different kinds of cars. You could have the real deal factory parts for less money.
Agreed, the SSBC front disc set is a collection of mismatched parts not properly sized/tested, I'd toss the booster and master set up for factory Mopar related pieces, the calipers/rotors are usable
I'd put a vac gauge on the engine manifold, chances are your running an automatic transmission?, correct? if so, and your manifold vac is around 10-12 inches, the first "braking" IN GEAR, will pull down the vac reading, and repeated braking after that renders the booster with no vacuum assist and no brakes, if this is the case then you might need a vacuum reserve canister, and or vacuum pump
