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Originally Posted by Vasilis
Also on the S2000 the car rear end wanders during hard braking especially on the AP1 models and are not the safest car to drive at higher speeds.
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This problem is *easily* mitigated by running MINIMAL rear toe. Perversely, the factory and many S2k owners think that running MORE rear toe helps. WRONG! Excessive rear toe (more than ~0.4 to 0.5 degrees total) on the AP1 makes it an evil-handling bitch that eats tires at an incredible rate. Setting toe to ~0.2 degrees total and the car handles brilliantly.
When I first tracked mine (Watkins Glen), I ran the max spec rear toe of 0.64deg total due to running front tires nearly as wide as rears, and because of all the warnings about it's tail-happy antics. Sure enough, I experienced weird, nonlinear handling that spooked me a little, despite years of experience in a much higher power/weight, sometimes tail-happy but always more linearly-handling 240Z.
Then I shared the car with a friend at Mosport. Day 2 the car became more and more oversteery, to the point that it was well nigh undriveable. Both of us experienced drivers in much higher power/weight rwd cars, both of us totally freaked by the cars spooky/evil handling.
Turns out the rears had already pretty much heat-cycled out!
Next event, I wanted to knock the toe down to min specs to get reasonable life out of my new rear tires, as I couldn't live with that kinda wear rate and I couldn't deal with the handling degradation at end of rear tire life.
I asked for the minimum AP1 spec: 0.32deg total rear toe or 0.16deg per side. Shop gave me 0.15deg TOTAL instead. I was quite worried at the next event that the car would snap oversteer all over the place. Instead, the car behaved MUCH better and more linearly. EXCELLENT!
Benefits of minimal rear toe: GREATLY increased tire life, MUCH more linear handling characteristics, LESS twitchy, but MORE responsive at turn-in, even improved mileage!
Excessive rear toe: SUCKS, for EVERYthing.
FFWD a couple of years, and at Mont Tremblant in the wet, the car was again almost undriveable! WTF! On the drive home through Montreal, heavy downpour, I had to slow to a crawl while cars around me were having no problems going 5-10mph faster.
Took it to the shop, lo and behold the alignment had shifted, giving 1.05deg total rear toe. I made sure they tightened the bolts adequately when they reset it...
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This was improved on AP2.
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Yeah, for the AP2 they eliminated almost all of the rear toe-change-with-bump that the AP1 suffered from.
Hard to believe how often the same exact mistake has been repeated with Japanese sports cars: FC RX-7, NSX, 2nd gen MR2, and then the AP1. The idea being that increasing rear toe-in with bump would make these cars *more forgiving*, as when you turned in and got some body roll, the outside rear would toe in and give understeer (or reduce oversteer). DUMB IDEA that NEVER ONCE worked as intended!
Very nonlinear handling, particularly over bumps. And if you make the rookie mistake of LIFTING off the gas when the back end starts to get loose, God help you! Because then in addition to unloading the rears, which gives more oversteer, you outside rear now toes relatively OUTward as the back end lifts, giving a huge additional dose of oversteer! Instant spin.
Anyway, the AP1 is a sweetheart with ~0.2 degrees total rear toe. A little weird, but not "out to kill you" weird. With excessive rear toe, it's really a terrible car to drive.