Quote Originally Posted by daveS53 View Post
In addition, the upper A-arm tilts quite a bit, while the lower is close to horizontal, at ride height. That causes the rubber boot on the upper to be squashed a lot, at ride height.
The upper arm is angled more than the lower arm to allow more camber gain on bump to prevent the outside tire rolling over on itself and keep the tread more parallel with the road/track surface.

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