Originally Posted by twohoos,Nov 9 2010, 01:39 PM

Just a follow-up on this since I took my car to Streets this past weekend. Bottom line is that my fears of understeer after putting a CR suspension in my AP1 were unfounded; in fact, with my setup, the car had significantly more oversteer than I prefer.

My setup differed from a stock CR in several areas, of course (not least the fact that the car's an AP1!). I ran AP1 16" rims with 225 front tires and 245 rears (RA1 R-compounds), as compared to the CR's 17" 215/255 RE070s. Also, I used my '00 rear swaybar (18% stiffer than the CR). Both of these differences would significantly shift handling balance toward oversteer. I have a rear bumpsteer kit on my AP1, so that aspect should be fairly comparable. Also, Streets is not a particularly fast track, so the aero differences should be minor. I'd just had a good alignment, including adjustable swaybar endlinks to eliminate side-to-side preload (weight jacking).

Over three sessions, I found the car twitchy under heavy braking, and (for an experienced but still amateur driver like myself) extremely loose in corner entry. Simple throttle lifts would induce nice drifts, and any amount of trail-braking threatened a spin. It was fun, to be sure, but ultimately not confidence-inspiring.

For my final session, I disconnected the rear swaybar. It was a bit of overkill -- more understeer than I'd like -- but the instability issues certainly disappeared. The car would still rotate easily under lift-throttle and trail-braking, and I could attack turns more aggressively. As a result, my lap times were 1.5 sec quicker (which is its own kind of fun).

That's not quite the end of the story, though. My data-logger showed that with the swaybar in place, my "best theoretical" laptimes with and without the swaybar were almost identical. That is, I'd been able to drive individual sectors of the track just as quickly with the bar in place, but hadn't ever put together a clean lap. Basically, with the swaybar it was just too easy to misjudge a turn and lose time in a big drift; similarly, the risk of a high-speed spin tended to make me brake too early and too much. On the other hand, mid-corner and exit speeds were a bit better. So, a *very* good driver would probably prefer the car's handling with the swaybar.

Next up: Same thing but with an AP2 rear swaybar (27% softer); same thing but with stiffer rear springs and no swaybar; and ideally (if I can find a couple thousand bucks) a "square" tire setup (255/255 front/rear) with no rear swaybar (and maybe stiffer springs).