GrantB

When my FRC C5 was up on the alignment rack last Friday, I pulled down on the rear sway bar to see how this affected the alignment. Much to my surprise, this seemed to toe-out the rear. Pushing up on the bar seemed to toe it in. So the car seemed to toe out during bump and toe in during droop. Bushings are brand-new Pfadts, so this change in toe must represent geometry.

Is this correct at normal (4.9" rear) ride heights? I suppose we may have been reading the machine incorrectly (the tech didn't seem entirely sure), in which case I'm accidentally running static toe-out on my car.

Caroll Smith referred to the rear toeing-out under bump as "roll oversteer" and called it a "violently unstable condition that must be avoided". While I'm not sure I'd call my car violently unstable, it definitely doesn't feel as stable under hard acceleration as other cars I've driven, such as Vipers that are bump-steered from the factory (via adjustment shims on the tie rods and steering rack).

If my observations were correct, are there any durable, race-proven (i.e., not going to break on me) tie rods that offer adjustable bump steer? I am familiar with how to measure bump steer. If no one else has done so, I may measure it myself to see if the car really suffers from roll oversteer.

Alternatively, does anyone know of any SusProg3D (or similar) files made for the C5 or C6 Corvette? If they exist, they'd answer my questions.

Thanks for any help.

mousecatcher

LG sells this: http://www.lgmotorsports.com/catalog...66d7eedbec063a however it doesn't say whether it's for front, rear, or either.

mountainbiker2

Those LG ones seem to short in length.

0Randy@DRM

It should be going the other way. As the rear tire goes into bump, the toe should be going in. LG kit will work front or rear, but something doesn't sound right and sometimes throwing parts at it doesn't help.

Set up a set of strings and measure the toe that way. Double check, the front of the wheel should be a bigger number.

Randy

Zip Corvettes

Last I looked we were the only ones that offered them for the rear, the whole unit anyways to replace the inside and outside.http://www.zip-corvette.com/Zip/prod...5C1A907F742F97

Lancer033

i've got them on all 4 corners, so they work on both ends of the car.

GrantB

Hmm, alright, looks like I'm be double-checking those results with some string then. I'm pretty sure nothing is bent, though I've only owned the car for half of its life. We've got some goofy camber discrepancies between RR and LR before, but eventually found out the alignment rack was on the fritz.

Thanks for the feedback.

bobmoore2

Grant,

Something isn't making sense to me here. Which part of the sway bar are you pulling down and pushing up? I'm asking this, because as I recall, the end of the sway bar moves up with a bump.

Bob

GrantB

I was just using it as a handle to move the sprung mass down, thats all. Obviously it twists a bit under bump.