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Old 05-21-2024, 01:37 PM
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n20ta2 n20ta2 is offline
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Default Front brakes dragging.

Completely new car from the ground up. As the title says the front brakes drag. Rear brakes do not, car stops just fine. I have an 8" trans am booster with a Bandit vacuume pump due to large cam but I'm not thinking that should cause any issues. Front brakes are factory style disc with a cast iron master cylinder and factory style perportioningvalve, I have adjusted the front brake pedal for a touch of play but it still drags. Does not pull left or right on braking just feels like I'm lightly applying brakes when coasting. When I jack up the car the front wheels do drag so it is confirmed. Car has 45 miles on it.

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1969 GTO street strip project 11.1 forged 461, highport heads
1995 Trans-am 420 ci sb 14:1 compression 9"ford
9.89@132 1.34 60ft SOLD!
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Old 05-21-2024, 02:46 PM
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I would suspect the brake flex lines not letting the pressure return to the reservoir. Have you tried cracking the bleed screw on a caliper to see if the brakes still drag?

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Old 05-21-2024, 06:35 PM
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Make sure the booster push rod is not too long.

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Old 05-21-2024, 09:15 PM
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I will check the pushrod from the booster to the master cylinder. I will also check the flex lines. Good ideas both.

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1969 GTO street strip project 11.1 forged 461, highport heads
1995 Trans-am 420 ci sb 14:1 compression 9"ford
9.89@132 1.34 60ft SOLD!
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Old 05-24-2024, 04:07 AM
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If you are running a reproduction brake booster, that is your problem. On these boosters the push rods are slightly too long. What I did on all my cars is put one washer on each booster stud before installing the master cylinder on the studs. One washer on each stud is all it takes to rectify the problem.

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Old 05-29-2024, 11:23 AM
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Ok haven't test driven it yet due to weather but this is what I found so far. I cracked the bleeders up front with no difference. I pulled the master off the booster and the rod was contacting the piston in the master before it was completely bolted up flush, probably less then 1/8 of an inch. I put a couple washers on the two studs behind the master. I pulled the calipers and greased the caliper slider inserts, they were tight and now move freely. I retracted the piston in the calipers and reinstalled,
I activated the vacuume pump to the booster and applied the brakes several times...seems to rotate with much less contact but haven't driven yet to build up any heat.

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1969 GTO street strip project 11.1 forged 461, highport heads
1995 Trans-am 420 ci sb 14:1 compression 9"ford
9.89@132 1.34 60ft SOLD!
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Old Today, 08:07 AM
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Thanks for all the ideas. Not exactly sure what exactly fixed it but after spacing the master and greasing the slides it's much better!

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1969 GTO street strip project 11.1 forged 461, highport heads
1995 Trans-am 420 ci sb 14:1 compression 9"ford
9.89@132 1.34 60ft SOLD!
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