Originally Posted by rayhuang
Have you guys played with track width much?
I ask because when I first built the car, I built it with 3m innner shims all around (for Jaco tires), but run Parmas so my car was ..umm... about 192mm or so. I rebuilt it with 1.5mm shims all around and was now shy of 190, but more to the point of al this, car got edgy with a high steering set-up on it (6 deg caster, low front roll) and doesnt seem t carry the corner speed it did when it was 192+mm. I am now again at 190. I added a black shim (0.75m) all around and may or may not get to test it for awhile.
I am hoping someone else test crazy has played around with this tuning aid.
Ray
What do you mean by 'edgy'?
Both ends being narrower will increase chassis roll. This is probably causing the car to dig in too much, ergo the loss of corner speed. And if by 'edgy' you mean that it is hard to be precise with the steering, then I'd suggest either of the following:
* If the track is relatively smooth and/or has tight switchbacks/chicanes, then I'd opt for stiffer springs all the way around (going up on all four corners in 2 to 3 lb increments)
* If the track is bumpy and the car is tracking very well over the bumps, then I'd opt for either raising the front and rear roll centers equally through the lower arm positions, or use front/rear anti-roll bars.
Making a decision on what to change also has to take into account where the car is losing corner speed. In tight corners (off-power or neutral throttle), more open sweepers (usually on-power) or all corners.
Posting your full setup info in the
online XRAY Setup Sheets would help us to provide better advice as well.
