I need your help folks.
I will spare you the long story.
My alignment shop is messing with my head. :banghead:
This is for a 99 C5.
Will people please confirm whether TOE-IN is a positive or negative value?
If TOE-OUT is the opposite.
And if it changes between front and rear.

Thanks all.


[Modified by jeffjor, 1:21 PM 4/10/2003]


[Modified by jeffjor, 1:22 PM 4/10/2003]

 

Jeff,
First stop :banghead:
Toe-in is a positive figure.
Toe-out is a negative figure.
Same for front and rear.
Straight out of GM service manual.
:cheers:
Dave

 

Grrrrr.
Thanks Dave.
My alignment is now bass-ackwards.
I have +0.05 toe in front and -0.03 in back.
I wanted toe-out in front and toe-in in back.
Looks like I have to try and get it switched first thing in the morning.

 

Hey Jeff,

Hold on a minute.
You want toe in in the front and toe out in the rear.
You can even confirm this in GM manual too.
Even racecars with this set-up is quite common.
So why do you think you want the other?

 

Jeff,
Mark is right. Your settings are within specs for the car.
I did not mean the front and rear had to be the same. I thought you were asking if toe-in was positive in the front then would toe-in still be considered positive in the rear.
My missunderstanding on that one.
The toe-out per wheel in the rear is 0.01 per the manual, which is very close to no toe.
If you reverse the settings you have, the alignment will still be in specs.
I will ask too, why would you want to change the alignment you have?
Dave


[Modified by corvette dave, 12:02 AM 4/11/2003]


[Modified by corvette dave, 12:03 AM 4/11/2003]

 

Thanks again guys for the info.
I confirmed with Chevy this morning that a positive value cause toe-in while a negative value causes toe-out. True for front and rear.

As for why I want toe-out in front and toe-in in back:
Putting some toe-out in the front will provide quicker turn-in and steering response. The inside wheel of the turn (the unloaded one) also ends up exaggerating the amount of turn causing some additional drag to pull the front in the direction of the turn.
Putting some toe-in in the rear helps reduce oversteer or loose rear-ends. By pointing the rear tires in a little, they end up pointing in the direction of the turn (or the front of the car) instead of having the loaded wheel pointing away from the nose prompting the tail to come out. It helps in keeping the rear-end anchored and in accelerating through the turns.
Too much toe-out in front and the car becomes darty and really wants to follow road irregularities. Too much toe either way in the rear and you start losing straight line acceleration.

I had this same discussion with a body shop owner who races. He did not believe me so he called a friend of his (the crew chief for Newman/Haas) and they told him the same thing, "toe-out in front and toe-in back is the hot setup for some road courses..."

Hope this helps answer the 'why?'.
Now I have to load up the truck and trailer to head off to Road America.
Thanks again all.




[Modified by jeffjor, 11:01 AM 4/11/2003]