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.
Step one is to put the Bilstein PSS9s on eBay before they're damaged in the dirt. The Corrado PSS9 kit has less total stroke than the stock shocks, which means no amount of re-valving will make them dirt-worthy.
With the money you just made, buy a set of Bilstein HDs, but don't bother taking them out of their boxes. Instead, go to www.bilstein.com, click on the Services link and follow the instructions for sending them in for re-valving. When you do, state that they're for a rallycross car and give your car's corner weights (go to a truck scale and weigh each end of the car) and spring rates.
About those spring rates... the simplest thing is to start with stock springs. Hopefully you saved those. If you need taller and/or stiffer springs, coilover sleeves can be added later, but you can also try stock springs from heavier Volskwagens that shared your Corrado's suspension.
Oh, and the anti-roll bars too. You want the individual wheels to be as free to move as possible, so they can maintain contact over ruts and dips, so go back to the stock bars as well. Don't put the big ones on eBay just yet, though. If you're struggling to get the car to rotate, it may be worth putting the big rear bar back on, or removing the front one.
If you want to stay out of rally tire classes, grab some snow tires instead. And if you really like doing this rallycross thing, you'd be wise to build at least a rudimentary skidplate, just to keep the oil on the inside.
Q Living Life In DI recently inherited a 2000 Civic with an automatic transmission for use as my winter car. I've only been driving it for two weeks and I'm already sick of rolling around with my left foot resting on the floor like every other lazy-ass American driver. Even more annoying is the violent mid-corner downshift thrown into any attempt at having fun on a tight curve.
Will it hurt my slushbox to downshift on corner approach? I'm not familiar with the electronically controlled auto trans, but it seems like sliding the gear selector from Drive to second or third would just send the trans the same signal the computer does when it's time to change gears. Something feels fundamentally wrong about downshifting an automatic and I wouldn't be asking the question, except that I have a not-so-intelligent friend who does it on a regular basis with no adverse affect (as yet).Brian BeefGeneva, IL
A There's a good rule of thumb to know if you're hurting anything mechanical. If there's any lurching, grinding, groaning, popping, squealing, or abnormal resistance, you're probably doing something bad. If you can do whatever you're doing smoothly, with minimal effort, you're probably going to be just fine.
Downshifting an automatic usually results in a lurch. Not good. That lurch is the transmission dragging the engine up to speed, and all that dragging is being accomplished through the slipping of some kind of bands, or clutches, chainmail, your grandpa's old leather belt, or whatever the hell it is that changes gears in one of those stupid things. Is that lurch-and the attendant slippage-any worse than the lurch when that piece of crap downshifts on its own in the middle of a corner? Not really. So it's probably within the transmission's design limits.
Beyond the wear, though, think of the smoothness of your driving. Do you really want to be lurching through corner entry just to avoid lurching through the apex? Hardly. Instead, try rev-matching that downshift. It isn't easy, but if you can predict the agonizing delay between your downshift signal to the engine room and the response of those oily little sea monkeys in the transmission, you can throw in a gentle little stab of throttle to smooth the whole mess out.