[mike72x]

hello! i hope someone can help me here because ive been working on this car for a while and cant get past the brake system. the problem on my trans am is that when i step on the brakes the cars barely stops. the pedal hit the floor as if there was air in the system. the term spongy brakes. the car has stock 4 disc set up. i changed the two rear calipers and the master cylinder twice. i bleed the system more than enough and yet no brakes. the only problem that i noticed is in the rear calipers. the piston is not keeping the brake pad close to the disc. its about a 1/4 of an inch away from each other.. is there a adjustment on them? i checked for leaks and found none. the only two things left to change is the booster and proportioning valve. but they seem to look good. its more of a pressure issue i think can someone help thanks

[2manyT/A'S]

I had this issues YEARS AGO when my 80 WS6 Turbo T/A was still fairly new,& as I recall,we had to crank the rear pistons out closer to the rotors to get any pedal.
My thirdgen T/A's with rear discs needed the same treatment,about every oil change (3000 miles)

[Dens71TA]

Have you used the parking brake? When the parking brake is applied it ratchets out the caliper pistons and takes up the slack. You need to use it regularly to keep everything in adjustment and prevent the rear calipers from freezing up. The '79-87 F-body rear disc calipers weren't the best design.

[Grand73Am]

Yes, work the park brake over and over until the pistons push out to the rotors.