Coil over springs-

[Mach 5]

I own a 1989 Pontiac Grand Prix and was looking for some decent high performing springs.

 

For starters, what is the rate and how much stiffer are the 95-99 springs from ST that are suppose to fit 1st gens?

 

Also what is better for the rear? I was looking at some springs that were 275 in/lbs. and some the were progressive rate 175-350 in/lbs.

 

What do I have to do to get the springs to fit in the rear? I believe that I need mounts but not so sure what to do?

 

Thanks.

[19Cutlass94]

You need coilovers for the rears as stock you do not have springs. 250lb spring rate is just about perfect, if you want a smootehr ride 200lb rate.

 

The ST springs are just about comparable to stock. A little bit stiffer but not by much.

[Mach 5]

what about the upper mount for the rear? Can I run the original or do I need something else? I know that I need a sleeve and adjuster. Is there anything else?

[19Cutlass94]

It is possible to run the stock mount. Youll need the adjuster nut, the sleeve, the spring, the strut.

[Mach 5]

but doesn't it have a chance of the spring popping loose? I guessing that others have done this.

[19Cutlass94]

No it doesnt. Take a look at the FFP coilovers, Held Coilovers. The adjuster nut is flat, and so is the spring where it meets it. Its the same thing at the top with the poly bushing. The weight of the car also helps keep it in place, as well as the strut.

[Mach 5]

cool, thanks for your help.

 

I think Im going to do a write up on this so nobody has any problems.

[19Cutlass94]

dont worry Im just about done with one

[Mach 5]

cool