The Formula and GT had 2 sway bars. The 4 cyl coupe had just a front sway bar. All other components are the same.
Spring rates are different. But there is no consensus on which springs came on which models. I've seen it across the board different. But generally the GT and Formula had stiffer springs.
1988 FRONT SPRING CODES --------------- -10048402 FPJ (Stiffest) -10048401 FPH | -10068654 ARD | -10068653 ARC | -10068652 ARB (Softest)
Some people claim that all the springs have the same rate but different ride height. I don't agree with that. My 88 Coupe suspension rides like a Caddy compared to my 88 GT. My Butt dyno tells me that there is a difference in spring rate.
[This message has been edited by jscott1 (edited 12-24-2013).]
Originally posted by jscott1: Spring rates are different.
Some people claim that all the springs have the same rate but different ride height. I don't agree with that. My 88 Coupe suspension rides like a Caddy compared to my 88 GT. My Butt dyno tells me that there is a difference in spring rate.
If you look up the factory specs for the springs (wire diameter, coil diameter, active coils, free length, etc) and do than math to calculate the spring rate you too will find that the fronts are all within 3% of each other. The rears are a little harder to calculate as the diameter changes from top to bottom.
Your butt dyno might be feeling the differences in wheel diameter, tire size, tire composition, shock choice, bushing compliance or some other aspect that impacts overall ride harshness.
Originally posted by fieroguru: ... Your butt dyno might be feeling the differences in wheel diameter, tire size, tire composition, shock choice, bushing compliance or some other aspect that impacts overall ride harshness.
I have heard that the 88 coupe front control arms had different part numbers from the GT/Formula control arms. Since the metal is essentially identical, this could mean that the coupe had more compliant bushings.
My main thought is if I have a chance to snatch up some 88 stuff, cradle suspension and maybe the front stuff, I wouldnt have to worry about which model other than V6. Mine is an 86GT
[This message has been edited by LornesGT (edited 12-24-2013).]
I would grab any 88 rear cradle. The sway bar can be added independently if you want. The 88 rear cradle is just about a bolt-in. (You'll need a couple of adapters and will have to change to coil-overs to provide enough clearance.)
The front is a different story. It can be swapped in, but it requires a bit of cutting and welding. More trouble than it's worth for most people.
Should of just bought an 88 but I wasn't aware of the changes and at the time, it was hard enough to find a rust free GT without expensive travel. It is what is is now and an 88 is in the future to keep original. I have looked at some company that offers a $1000 change to coil overs in the front found on this forum. At some point I do want to make it the best I can 3800 or V8 and all that.
