Subframe 73 With suspension of 78
 

I have done some changes to my Sprint 73, I used a 78 TA subframe. Question I have to use the suspension of 78 or 73.
There is some difference between the suspension 73 and 78?

Upper Control Arm?
Lower Control Arm?
Center Link?
Tie Rod Ends?
Pitman Arm?
Idler Arms?
Joints?

IIRC, the only difference is with the disc brake rotors, which I believe will require matching spindles.
The spindle and rotor changed somewhere around 1978-79, but I can't remember exactly.

The lower control arms changed(and possible the spring pocket in the frame too) in 1977 as they require different springs. I think they changed again in 1979 when the spindles with the larger wheel bearings were introduced. I noticed my old '81 Trans Am had a much tighter turning circle than my '71 and '73 Trans Ams. The backside of the control arms looks to be more notched.

The center link and tie rods changed around 1975. The best idler arm is the '70-71 style. It uses a bearing. Later styles used a threaded rod and screw up and down as the wheels are turned.

how did you get a 78 subframe to fit a 73 body?

dens71, tell me more about the idler arm differences please.
to help the original poster, birds switched to the big-car caliper in 79.
spindle is different, one ball joint is different if i recall, rotor is different, one wheel bearing is different.

I 2nd that question, because wasnt the 73 subframe longer by a few inches, like where the bolt holes were?

To if I did it.