I have an 83 z28 with four wheel disc. The front two calipars have just been replaced. The rear probably needs some help but has 1LE brakes. Aside from all this, the brake pedal is about as hard as a brick to press and even if you stomp on it it will take a lot longer than it should to stop the car. After working on the front brakes the car stops a little better at higher speeds but at lower speeds I almost have to reach for the E-brake to get the thing to stop. Is my power booster dead or how would I check if it is. Otherwise, what else may be the cause of my crappy braking?

 

Check all your vacuum line running from your manifold to your PB Booster if you haven't already done so.

JD