will the trans am suspension package froman 85 fit on my 91 camaro both have same drive train 700r4 305 tbi

 

Yes, but is the 85 suspension high mileage? Also, how are the bushings? I'd be careful about swapping in old/used suspension parts.
I also have a 91 camaro, rs, odo is up to 115,000. After replacing sway bar bushings at about 100,000 miles, the handling increased so much it felt like a different car.

EDIT: I just noticed this should be in the susp. forum.

 

As mentioned the parts will swap over but I would not use the springs, shocks or struts unless they are new. I would only look at using the sway bars. Everything else is basically the same (panhard bar, LCA).

 

Not sure about the trans am lower control arms, but the IROC lower control arms are different thant the RS units. They have (aluminum??) stiffener/spacer bolted into the inside of the arm. At least both my IROCs have them. Never check the Z28, but the 91 RS definately didn't have them. If I could find the old ones for the Formula (WS6 suspension) I check them as I didn' t really pay any attention when we pulled them off.

 

My '88 formula doesn't have the "stiffners".

It has the WS6 setup, which I believe is the same as the trans am's.