Ground Control Coilovers - Dear Dave - Geek-At-Large

Q: How To Fix Coilovers With A Hacksaw
I have a 1993 Sentra SE-R with KYB AGX shocks, Ground Control coilover sleeves and Eibach race springs. My front springs are rubbing badly against the coilover sleeve and eating away the thread on the collar. What can I do to correct this?David CabanBellevue, WA

A:Your problem is extremely common and should be relatively easy to correct. Any time you compress a simple coil spring like an Eibach ERS, it will tend to bow to one side slightly. This can be caused by upper and lower perches that aren't completely parallel, but will often happen even under perfect conditions.

There are two solutions. The hard way is to replace the straight springs with barrel springs. Barrel springs bow outward in the middle, giving them a barrel-shaped profile. The top and bottom coil will still be 2.5 inches to fit your existing perches, but the coils in between are around 2.75 inches in diameter. This gives enough clearance for the spring to do its natural bowing without hitting anything.

Ground Control carries several sizes and rates of barrel-shaped springs, but the selection is smaller and the part numbering system less intuitive than the standard ERS springs, so there's no guarantee the spring you want will be available.

The easier solution (and the one that's closest to free) is to remove the threaded collar and cut off the part the spring rubs on. You're never going to raise the car high enough to need this part of the collar. To make yourself feel better, count this as a reduction of unsprung weight.

While the suspension is apart and the hacksaw's in your hand, make sure the collar is as close as possible to concentric with the strut tube. Most Ground Control sleeves have two alignment rings machined into the ID of the tube to help the sleeve fit snugly on the strut body. Make sure you don't cut off one of these rings. If it's in the way, be sure to leave at least a little bit of the upper ring, or you'll introduce a whole new assortment of noises to your suspension.

Q: Autocross To RallycrossI bought these sweet Bilstein PSS9 single-adjustable coilovers for my 1991 VW Corrado G60 to replace my rusted stock set-up. I also got stiffer anti-roll bars and polyurethane bushings. I intended to take the car autocrossing and have a balanced suspension for the street.

Fast-forward three years and I've bought an S2000. The Corrado doesn't get driven much and, sadly, never autocrossed. Then I discovered that my local SCCA was hosting a rallycross event. So I took the Corrado, with Toyo Proxes-4 all-season tires, and the suspension set to full height and full soft. It survived four trips around the course, but it wasn't an ideal situation. The suspension seemed way too hard, bouncing off even the smallest bump. Nonetheless, I loved the rallycross experience and plan on doing more next season.

Should I get the PSS9s re-valved and re-sprung with more appropriate settings? Unfortunately, given the car's age and relative rarity, there aren't many others who have prepped it for rallying. Do you have a good starting point for setting the car up right? Should I remove or replace the very stiff (25mm front, 28mm rear)anti-roll bars?Mike DirtskiBaltimore, MD

A: Welcome to the addiction called dirt. Before long, it'll be the S2000 making a brown patch on your lawn.

Your Corrado is not as unique as you imagine. Being basically an A2-platform VW, the suspension is closely related to Golfs and Jettas of the same vintage. There are plenty of people rallying those successfully and most of their suspension parts should fit your car.

On the other hand, you don't need to go to the expense of a full-blown rally suspension just to have fun rallycrossing. You need a reasonable amount of suspension travel, good damping, and a set-up that encourages the tail to slide around a bit.