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      11-13-2012, 02:09 PM   #16
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Originally Posted by bigjae1976 View Post
For the engineering geniuses here...

The toe arm (#1) runs forward and is curved outwards. So if the suspension compresses, neg camber increases but I can't explain what happens to cause the rear to start to toe out or in.

Versus the E9X which has the toe arm (#13) at the rear of the hub so use the suspension compresses, that link should elongate and push the back of the out creating toe in?
In my opinion it is not possible to determine anything from those diagrams. The exact location of the attachment points, angles of the arms relative to each other, etc... are all required to make any assessment on toe changes. Even then, it would be extremely complex. A full computer simulation would be the only way to tell besides actual measurements on the car.

I can understand why more camber is required when the suspension compresses, it is to counter the effect of body roll. To keep the tire as perpendicular as possible (or with some negative camber) relative to the road even as the body rolls.

However, from the latest info I have read, toe is better when kept constant throughout the suspension travel. Toe changes can make the car's behaviour less predictable. This is contrary to my original intuition, so will try to dig some more .