300z front brakes searched

[r32gtr]

Ok I am having a slight problem here. I have an 89 non abs coupe. I upgraded my front brakes to the 300z brakes and the master cylinder last spring. They were fine when I first installed them. But then my booster went, apparently the old bmc was bad. So I replaced the booster with a new one for the car. Well since I did that, my brake pedal has had barely any travel. basically you push a half/inch and that is it, the pedal is solid. However I am able to stop the car just fine. I want to get my pedal feel back to where it is supposed to be. Does anyone know what I need to do. I bought the brakes/rotors and bmc off a kid on a local forum, so I am not sure of the size of the bmc, is there a way to measure it? Cuz I have read on some topics on hear about adjusting the booster piston, or certain sized bmc's and people have no problems whats so ever. I have also read about people putting the s14 rear calipers on their car's and that seems to help. My mechanic told to source the 300z proportioning valve, which I found out that it is built into the bmc.