Meh. Take any car that's neutrally balanced, load it up at 100% cornering and lift off the throttle suddenly. It's going to step out on you when weight transfers off the rear axle. Simple physics.

One thing that's commonly mentioned with the S2000 is that rear toe changes as the suspension compresses. It's supposed to help the car turn, and it certainly does promote rotation. I think a lot of people let this get them into trouble and then fail to hang on. Then they widely abuse the car as being overly "tail happy".

Truth is, it's a pretty damn neutral car. Even as a track novice, I found my S2000 very easy to control. Even when I did get it sideways, it was fairly easy to catch. That said, my car has Bilstein PSS9s, so there's less suspension movement than a stock S2000, which mitigates the toe changes I mentioned above.

 

Another thing I'll add to my own post...Honda changed the spring rates and sway bars on the S2000 every year or two, in part to control the oversteer tendencies. Early models were significantly stiffer in the rear, later models flipped that. Stiffer front bars/springs help keep the rear end planted. The PSS9s on my car, interestingly enough, have roughly the same F/R balance as the later CR suspensions.

Numbers here:
https://www.s2ki.com/s2000/topic/960...way-bar-rates/
https://www.s2ki.com/s2000/topic/512...-spring-rates/

 

Difference between ap1 and ap2: https://www.youtube.com/watch?v=hkcC2uzcQgk

The Ap1 definitely has snap oversteer. Sometimes when I take a fast left turn on the street the rear end will kick out. AP2 had less of this, more neutral but nothing sway bars cannot fix

 

I think the AP1 is a ball on the track. You need to ditch the crappy all season tires asap. Get yourself some summer tires and go up to 245 on the rear. Once you get on the track you'll learn to use the car. You can judiciously lift off the throttle in tight corners to rotate the car, then step back on the gas to plant the rear. I run mine completely stock with the exception steel brake lines and upgraded fluid.

 

My Miata is +/- 0.1% for Front-Rear, Right-Left, and Wedge weight distribution with me in it and I never had lift-off oversteer. I understand the unloading of the rear axle can be a dynamic problem during limit turning. But, I wonder if what is striking me as a "happy" rear end is more to do with the toe-in changes due to suspension compression.

Is there anything on this car that needs to be bullet-proofed before a genuine track outing? My 2009 STI had brake and cooling issues. The stock DOT 3 fluid will cook if you drive it like you mean it, and the ridiculous naturally aspirated Impreza radiator is completely inept at cooling the STI motor, and oil due to the turbo. I was taken back to learn all three Imprezas (N/A, WRX, and STI) had the same radiator for that year; 3/8th inch single pass with plastic ends... Lame.

Thanks for the links JeffBrigs. Are all years for the S2000 sway bars dimensionaly the same with the exception of diameter? If so, I could potentially mix and match for a good setup on the cheap. What I mean is put in a 2000-2002 or 2008-2009 front bar to dial back front grip and balance out the oversteering.

 

The AP2 has a thinner/softer rear bar, so you could try that and/or the AP2's thicker front bar. It's kind of cool that there are so many different combinations available just using stock parts.

I did my first track day completely stock (minus upgraded pads, hoses & fluid), including OE S02s in the stock 205/55/16 and 225/50/16 sizes. Then I did my second track day a month later at the same track, but with Michelin Pilot Super Sports in the stock AP2 sizes (AP2v1 wheels), 215/45/17 and 245/40/17. You can see that the width balance is a little more understeer-biased with the AP2 setup. Frankly I thought it handled very much the same (maybe my butt chassis dyno is insensitive?), although I have yet to look at size-specific specs for the PSS tires, maybe the 215s are wide and the 245s are narrow for their size, I have no idea.

Spring/damper/bar rates are more important/effective for fine tuning handling. Even by changing tire widths, the contact patch is going to be basically the same size.

 

Check the AP1 retainers for cracks

 

Definitely pads & fluid. I upgraded mine before setting foot (or tire) on track, but I've heard the stock pads don't do so hot (or cool?) on the track. I believe I ended up with Carbotech XP8s all around (maybe XP6 rears, I forget) and they were perfect with ATE Superblue (no longer made in blue, just gold) fluid.

They do have a tendency to crack rotors, so it's a good idea to bring spares and tools with you. Didn't happen to me with my 50k mile car, but next time I'll probably bring some.

Otherwise just keep it topped up with oil, give it rest between sessions, and it should perform flawlessly.

 

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Check the AP1 retainers for cracks
[/quote]

Are you referring to the caliper retainers?

 

Handles fine to me at its limit, going pass its limit is the issue. Every S2000 at autocross events will be set-up differently, it's best to ride with as many ppl as you can and try out what they do and see if it works for you. Alignments and tires are big #1s, then other things like brakes, a master cylinder brace to reduce flexing, tire pressures, etc