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Old 06-12-2007, 04:44 PM   #23
thenorm
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What I Drive: '04 liquid grey ZX3, built for FSP

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Quote:
Originally Posted by S1lkwrm View Post
Assumptions:

- turn left and the suspension rolls right and rear right tire toes out and I think rear left toes in causing the rear steer.
umm, isnt this backwards? when u compress the suspension, the tires toe in. This has the effect of lessening the yaw (rotation) induced by sudden steering imput.
The suspension is designed so that Joe Shmoe, when he panic turns around a dog that runs into the road, doesnt loop it into a telephone pole. It was not designed to improve turn in for racing. It is an economy commuter car afterall.

If you look at the control arms of the rear suspension, you'll see that the control arm towards the front is short than the rear, when the suspension compresses it has a shorter arc and it esentially pulls its part of the "blade" trailing arm towards the middle of the car. this flex of the control blade is what toes the tire in on suspension compression.

That why after I lowered my car, my rear toe visibly pointing in.

to modify the PRS, you would need to change the starting position of the front control arm. If it started out aimed downwards instead of horizontal, the inital swing of the arc would push the control blade out (causing toe out), then as it passed horizontal would pull the blade back in (toe in).
if that makes sense to anyone else


umm ya, jsut noticed this was a dead thread that i was responding too, but too late now. this info is still important
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