Hey guys,

About six months ago I installed a nice rearend from a '96 TA into my '91 RS. I loved it. Still do. But I immediately had one problem and I'm not necessarily satisfied with my initial solution. I think it's time to revisit that.

It's common knowledge that if you perform this mod and your wheels aren't 4th gen offset, you're going to have them stick out nearly 2" further than stock. In my case it put the sidewall about dead even with the end of the fender lip. I knew this was going to happen, and it really doesn't bother me much. At worst it looks a little different, at best it might even help with cornering, who knows?

I expected all that. What I did not expect was just how worn out my rear suspension was. As soon as I got it off the jackstands I did a celebratory two-wheel burnout, confirming my new posi, and proceeded toward the highway for a road test. It was all so beautiful until I crossed the first speed bump. I think you know where this is going. Fortunately I did not hurt my quarter panels. I did cut up my sidewalls, particularly on the passenger side. I was not amused.

I needed to fix this immediately, and cheaply, so I went and did the first thing that came to mind. Air shocks. And that worked great. Hasn't been a problem since. I'm not a fan of the jacked-up look, but the shocks are good and stiff, and it's nice to know there's just that much more travel before disaster strikes.

But air shocks can't be good for a unibody, and besides, it's all jacked-up in the rear now. I don't think it looks good. But if I let enough air out of the shocks to even out the ride height, it gets too soft and I get worried about those speed bumps again.

Now for the whole point of this story. Here's my dilemma: If I put a good pair of normal shocks on there, am I going to fix the problem or am I going to ruin my new tires? The shocks I replaced were definitely blown, both of them. Useless. But could it have been my springs too? I'm pretty sure they're original. I suspect I could just put some good shocks on there, but I am going to be rather upset if I'm wrong.

I was thinking I should get the Moog CC635 "cargo coils". Anybody have experience with these? Or would I be happier with the 5665's, which are listed as stock replacement for the IROC? Do the CC's raise the ride height ridiculously, thus defeating my whole purpose?

Here's the rest of my setup: Formula GP struts (NOS) on decent factory springs in the front, IROC swaybars with poly bushings, fresh 245/50/ZR16's on the front and 255/50/ZR16's in the rear. It rides like a rock and handles absolutely great, I just can't stand that excessive tilt.

I know I'm not the only one who has this problem. What are you guys doing about it? (Besides the obvious - Ideally I know I should get new wheels.) Is stock-type suspension good enough when it's in decent shape? Should I get new springs? Or have I pretty much done the best thing already? Thanks!

 

There's no such thing as "decent" factory springs on these cars.

Your front springs are just as used up as your back ones.

You'll also find, the Formula GPs wont' last real long. That's one of the reasons they're not on the market any more. Watch them carefully for fluid leaks: when you see fluid, they're done. My brother's couple of sets didn't last more than 10,000 miles each before they started leaking.

The CC635 rear springs work fine. They will however not fix the problem of the wheels being in the wrong place. The wheels will still hit the fenders, maybe just not as often or as easily if you're lucky.

You need to get the right wheels, if you want a solution, not a "
fix".

 

I've heard about the leaking problem too, but for what I paid for the FGP's, I figured they were worth trying. If they die in a few months I got my $30 out of them, and I might even get another pair if I still can. The front springs I might replace just for the hell of it when I do the rears, but they really are okay. I'm not even totally sure that the rears were shot, I just don't want to risk it.

Whatever I do, I know the best thing is to get new wheels. I wrote that in my first post. But that's not happening in the immediate future. I know people do this all the time. Could somebody who's running like this share some experience?

Thanks.

 

1st - shocks won't solve any of the problem. Shocks don't have anything to do with ride height (unless they are air shocks that are working with enough pressure to work against the spring) - they only stiffen or soften the "recoil" after the spring has been collapsed (ie hit a bump).

It's the springs that you need to look into. You need new stiff springs. I have a 2002 LS1 rear in my 1992, and with the Eibach Pro Kit lowering springs (lowered 1 inch), I rarely bottom out (although it does happen on occasion with enough bump). And passengers make a great effect as well - easy fix there - leave the kids at home!

So if you are bottoming out on stock springs, you really need new springs bad.

One other possible option that I have considered, might be adding another spring isolator (or something similar) in the top of the spring - that might buy some additional room.

Or, Just don't hit the bumps so hard!

 

I'm actually surprised and encouraged that you lowered it and don't bottom out. I don't either, but but that's because of the air shocks. I guess they're basically standing in place of decent springs.

I think I know what I'll do. I'll try the CC635's. I'll drop the pressure on the air shocks and see if that evens out the ride height without allowing it to bottom out. If it does, I'll be confident about spending the money on good performance shocks instead of this rock-hard truck stuff. If it doesn't, then I'll just put the air back in and live with it until I find a deal on some wheels at a time when it makes sense. Thanks for the help...