[77TA]

I am putting a factory rear disk brake system on my 77TA. It came from a 80 TA I was told . The passenger side bolted up nice and easy. the driver-side caliper mounts low and in front and the parking brake arm hits the spring perch and I can't get the holes to line up and if I did it would bind things up. Any Ideas whats up ??
I am thinking I will have to grind or cut a portion of the perch off to make it work. PITA
and this is factory system !!!!!

[77TA]

I am putting a factory rear disk brake system on my 77TA. It came from a 80 TA I was told . The passenger side bolted up nice and easy. the driver-side caliper mounts low and in front and the parking brake arm hits the spring perch and I can't get the holes to line up and if I did it would bind things up. Any Ideas whats up ??
I am thinking I will have to grind or cut a portion of the perch off to make it work. PITA
and this is factory system !!!!!

[Skip Fix]

Something isn't right. The parking brake arms are side specific. Usually also the calipers have a L or R on the stud for the adjuster arm to bolt on.
The pull arm pulls to the front so you may have to be sure it isn't fliped over.

[rolling money pits]

did you just get the calipers and mounting hardware, or was it the entire rear axle?

i do believe the axles were different between the disc and drum set ups. so, if yours was a factory drum car, and youre swapping the disc hardware, you might run into issues.

skip is correct, the calipers will mount opposite to one-another. make sure the mounting plate is on the axle tube in the proper orientation. that also might be the source of the interference.

btw, i hope you also got the proportioning valve, booster and master from the TA. if you didnt, youll need to get them. you could possibly get by using the same booster, but the other two are a must.

are your rear rotors new, or turned?

the calipers are mothers, they are notorious for leaking at the parking brake pawl. if you havent, get a rebuild kit for nothing else, the multiple seals for that. i think it consists of a opaque nylon washer, a rubber encased steel washer, and a plain old steel washer.

i think they go on, first nylon, then rubber job, then the steel one, the parking brake arm.

youll need to make sure the parking brake mech is working correctly, and you use it EVERYTIME you park the car.

[77TA]

Yeah I was converting from drum to disk. I thought they were the same though. I was careful to put the arms on just as they came off the old calipers and I put the seals on. The nylon then the rubber. There was no steel on the old caliper and there was nothing in the box like that. There was a couple of small o-rings that I did not see a use for though. I am thinking I'm gonna have to cut the perch a little to make it fit at this point, I thought this was gonna be a easy swap !!!!

[rolling money pits]

i hear you on the PITA factor.

i had a complete axle, disc to disc, with booster/master/valve. all for $120.

was gonna put it into my 70, easy enough, right?

wrong!!

one week later, after two sets of calipers and a few phone calls to Cardone, making/bending up EVERY SINGLE brake line on the car from MC on back, getting a new brake pedal, several pressure bleeds, a shortened driveshaft and a differential rebuild cause of wasted bearings i was finished!

seriously though, sometings not right on yours, and i wouldnt go cutting/grinding on that spring perch. something is bent or on incorrectly. do you have a service manual that covers the disc brake firebirds? if not, get one, or get something with an exploded view. they also have different parking brake cables between disc and drum rears. you did get disc ones, or use the ones off the rear?

[Skip Fix]

Here's a couple of pics

[Skip Fix]

Another, both are of passenger side.

[Skip Fix]

Sorry those are actually driver's side.

[77TA]

Its almost like my backing plate is clocked about 30 degrees further counter-clockwise on the drivers side or something. I will try and take picture tomorrow.

Thanks for the help.

Oh how is the parking brak cable routed I tried routing through the drum brake hole in the frame on the passenger side and its real tight and about 1 inch to short it seems.

[77TA]

I just got done swaping the plates and all is well !!!!

I did not think the driverside should have been clocked so far down. The pictures were a great help thanks !

[Skip Fix]

I just wish they had locked the passenger side a little more to take the caliper bolts out easier without having to loosen the backing plate! May 5 degrees difference!

[77TA]

I got another question. Are the caliper bolts the same as used on the front calipers ?