It was a miracle Project S2000 made it from San Diego to Los Angeles the day we bought it. The stock rear S-03s were so worn on the inside that there was no longer any rubber visible, the remaining steel belts actually reflecting headlights of the car behind.
Like any enthusiast would, we took the worn tires as the perfect excuse to splurge on some new wheels and rubber. Mackin Industries had just the rollers for the job: a set of black Volk Racing TE-37s. These days, people like to run 18-inch wheels or bigger on relatively small cars like the S2000. But since ours is going to the track, not MTV Cribs, a one-inch diameter hike to 17 inches is perfect.
Off the shelf, it's tough to beat a good ol' fashioned TE-37 when it comes to light weight. The 17x7.5-inch front wheels weigh 15.6 pounds a pop, and each of the nine-inch wide rears weighs 17.1 pounds. Combined with the higher profile afforded by 17-inch rubber, the forged wheels should be pretty much indestructible on the road. And while we're not exactly sticklers for aesthetics, they look pretty darn good, too.
We decided to wrap our new metal in a set of BF Goodrich KDs measuring 225/45R17 up front, and 255/40R17 in the back. This front-to-rear ratio should keep a similar balance to stock, while adding a small safety margin to guard against the snap oversteer that plagues 2000 model year S2000s. We stayed relatively conservative with the tire compound for now, in an attempt to keep the car streetable and match grip with engine output. In the future, we'll install a host of power enhancers that will necessitate the increased traction offered by R-compound tires. When that time comes, we'll swap out for BF Goodrich's new (to the US) R1.
It's tough to improve on the stock S2000 suspension. The car comes with external reservoir shocks that, combined with well-chosen spring rates, make it pretty capable in the twisty stuff. But since we were about to add a couple of pounds of unsprung weight to each corner, we needed something with quick reaction time and good rebound damping. Something a little more geared for track use.
The answer came in the form of KW's Variant III coilovers. Built for the weekend racer, they offer independently adjustable rebound and compression, and we can pick our own spring rates before they get here. Given the wide range of adjustability and KW's reputation in racing, they should help fling the S2000 around The Streets of Willow, our local race circuit. And thanks to the stainless steel construction and the preset high-speed damping curve, they might actually be bearable during daily use.
We decided to stick with the recommended spring rates, which meant 515lb/in for both front and rear. The spring rates being equal may cause a pogo-stick effect at certain speeds in a car with a 50/50 weight distribution, but we're willing to take the chance in exchange for retaining the neutral handling of the stock suspension.
Due to the limited travel of the rear suspension and the arc in which it travels, it's important not to go too far when lowering an S2000. KW allows for an adjustment range of 1.2 inches in the front, and an inch out back. That doesn't refer to how much lower the car gets to the pavement, it just means we can raise or lower the ride height over a spread of 1.2 inches or one inch, respectively.
You can make the car higher or lower than recommended by a small degree if you want, but KW suggests that the shock would then be out of optimal operating range. Based on the results we got when working within the recommended range, we see no reason to set the coilovers otherwise.
M-Workz in Gardena, California, is the end result of a lifetime in cars for a guy named Steve Mitchell. He's raced and built cars professionally for decades and he's spent the past 18 years at Nissan, engineering every imaginable aspect of its cars. So we figured he could handle the task of installing our suspension and corner-balancing the car.
The Wheel Supply in Industry, California, handled the task of mating Volk to BFG. We installed the finished product and took a quick measurement of the wheel well gap-we didn't want to stray too far from stock. There was a 2.75-inch gap up front and a full three inches in the rear. Mitchell got to work dismantling the stock stuff and installing the coilovers.
Installation couldn't have gone smoother. Mitchell likes to whistle while he works-incredibly irritating for any journalist who might be taking pictures, but at least it's a sign that he likes what he does. Springs mounted on shocks, we were ready to mount the suspension. The front was a bigger pain in the ass than the rear, as the upper A-arm had to be removed in order to slide the spring/shock assembly in (and slide the old one out). The rear shock and spring on the S2000 sit behind the moving geometry, so barring digging through the trunk to unbolt the strut towers, installation and removal was much more straightforward.
Suspension mounted and height loosely guesstimated, it was time to move on to corner balancing. "There's a critical step many tuners miss when corner-balancing a car," blurts Mitchell. "It's called leveling the floor. It's common sense, really. If your car is sitting at even a slight angle, weight is going to be shifted down the slope, toward the lower end of the car."
Armed with his laser leveler, Mitchell aligned the four tables that would support both the scales and the car. His have additional run-off area (roll-off pads), so the car can be adjusted and rolled on and off in a snap. We still weren't ready to start. Mitchell laid a towel down in the driver's seat before loading my exact weight in sandbags (that number to remain confidential).
When the S2000 first hit the scales, we recorded 2974 pounds-with a full tank of gas and the sandbag fat-ass in the driver's seat, which means we have an unnaturally light S2000 on our hands. According to the US Department of Energy, a gallon of gas weighs anywhere from 5.8 to 6.5 pounds. Let's call it 6.15 pounds. The tank's 13.2 gallons, so figure on about 81 pounds in gas alone. Tack on the sandbags, which, I'll regretfully admit, weigh 200 pounds, and we have a total weight of 2693 pounds. Like I said, a light S2000. Oh, and yeah, I'm on a diet, so you can all just stop writing the e-mails now.
What we're concerned with, though, is weight distribution. As it sat, the car showed a cross weight distribution of 48.8 percent from right front to left rear (and 51.2 percent from LF to RR). Not bad. When we were done, we had managed to equalize the cross weights for near 50/50 distribution. We adjusted the front spring perches to 60mm and the rear to 50mm, closer to the low side than the high side of the adjustment range, but nowhere near over-lowered. The wheel well gap had shortened by 1.5 inches up front and an inch out back, for a total gap of 1.25 and two inches respectively.
Before we sent the S2000 back out into the wild, we wanted to figure out what had caused the inside of the stock S03s to wear so rapidly. Unsurprisingly, the toe was way off, measuring a remarkable 9.5mm toe-in on each side, which is about 3.5mm out of max spec. And that's a ton. Often, the toe is adjusted in an attempt to compensate for the car's natural tendency for sudden oversteer, when the rear suspension compresses. After double-checking the front toe at zero millimeters, we took the toe back out to max stock specs (6mm a side). Because put simply, over-toeing in the car is a crappy band-aid for the real problem, which is toe-out under compression.
The first test of the revitalized S2000 was on the rugged roads that surround M-Workz. We left the rebound and compression at their factory recommended settings. We were utterly shocked to find that the ride was, if anything, smoother than stock, absorbing imperfections in the road without overreacting to potholes or large dips. At the same time, there was no perceptible body roll. It'd take a day at the track to really dial the suspension in, because for street use, it was more than capable.
And so we took the car to the Streets of Willow for a few shakedown laps. Right off the bat, the car was brilliant-even Mitchell was impressed with its ability to turn in and carry speed through technical sections. After messing with the coilovers for the better part of four hours, we ended up hovering right around the factory settings. A further quarter-turn of rebound up front was all that was needed to perfect the set-up for Streets' bumpy surface.
Does the car oversteer? Yep. But we're not going to dull its responses by toeing in the rear. We'll tame the rambunctious tail with a bump steer kit, but that's for another installment.
Before putting the S2000 away wet, it was off to our proving grounds in Fontana, Cailfornia. It was positively adjustable through the figure-eight test course, slight lifts of the throttle rotating the car around to find a perfect line in and out of the long corners. When the dust had settled, the S2000 net a 25.9-second average. To put this in perspective. A stock 2006 WRX runs the figure eight in 27 seconds and a Porsche 911 (997) GT3 will do it in 24. On the skidpad, the car managed an impressive 0.9g.
As hard as we try, we can't find the need for any further suspension modifications (short of a bump-steer kit). Thicker anti-roll bars would do nothing to improve the car's perfect balance. Amazingly, we seem to have conquered the suspension situation in one installment. Watch us attempt to tune some individual throttle bodies from Fuji Racing next time around.
Photo Gallery: Honda S2000 Project Car - Sport Compact Car
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