I do have to disagree with the assertion that the tie rod must be horizontal, as that is not at all the case.

What does have to occur is that at normal ride height, the 3 imaginary lines drawn along the upper A arm, the tie rod, and the lower A arm must intersect at a common point.

See the diagram below.

If that is the case, bump steer with be nil, regardless of the angle of the tie rod or control arms. Unless you are changing ride height significantly over or under the design ride height, then bump steer should be fine (assuming the steering kit has been installed on early cars). I should also mention here that changes to camber (which occur with ride height changes) and caster that require changes to the tie rod length to maintain toe can impact bump steer, but only if the length change is relatively large.

Fortunately for most owners the M3W suspension is not adjustable for camber and caster so it's hard to screw up. All this assumes you are only raising or lowering the ride height +/- an inch or so. If you are going say +/- 2" or more from stock then it would be worthwhile to check and adjust bump steer as required.


[Linked Image]

BTW-the diagram was taken from this article (https://www.onallcylinders.com/2014/06/27/correct-bump-steer/),

Last edited by Bitsobrits; 04/11/21 12:29 AM.
Steve
Late 2012 M3W