Quote Originally Posted by Tamra View Post
I think most of the 818 platform's tramlining issue is due to bump steer problems, assuming your alignment is already correct. I'm sure power steering can help cover up some problems.

Based on our recent measurement of bump steer problems on this car (about 3/4" of toe in at 2" of travel), I imagine a lot of 818S owners are experiencing extreme toe changes under bump travel.

The resulting alignment change wouldn't be present at static ride height, so your alignment shop would probably say you are fine... but then you hit a bump, and your alignment is nothing like it was, resulting in severe toe changes and tramlining.

We are running 500lb springs on the front of our 818, so it impacts us less due to the fact that we are getting less travel due to the stiffer springs. But if you are running softer springs, I imagine it would be amplified.

The 818R manual has a bump steer fix included, but nothing is mentioned in the regular manual.
you are running an S at R height tho IIRC. Did you measure bump steer at normal height?