The length of the inner-to-outer tie rod must be equal to the length of the lower control arm (pivot to pivot). They must also rise and drop in a parallel plain. Anything different and you get a change in toe as the suspension goes through jounce and rebound, in other words "bump steer".

The outer tie rod can be shimmed toward or away from the knuckle to obtain the parallel travel, but a rack-n-pinion (inner/outer tie rod) that doesn't match the length of the lower control arms gets a little more complicated.

You can heat and bend the lower ball joint arm up and down or inward or outward to help achieve the equal length and parallel, but only so far.

The Mopar chassis book shows you how to graph changes in toe throughout jounce and rebound and how to correct it. It works for any LSA suspension, but with miss-matched parts there may be only one solution and that's to purchase parts that are engineered to work together.

When it's all said and done camber should be at or near zero regardless. Cross-camber and cross-caster should be less than .5 degree. Preferably zero for a flat track. Excessive positive caster will cause rapid wheel shimmy. You need only enough positive caster to maintain directional stability.

One last thing. Excessive positive scrub radius will put an excessive load on the suspension components and could be a cause for flexing and cracking.

Positive scrub radius occurs when the alignment of the upper and lower ball joints meets the road inside of the point at which the center of the tire meets the road.

Positive scrub radius results from using smaller diameter wheels and tires and/or using a wheel that has little or no offset (common with front runners).

Some positive scrub radius is OK; it's the excessive that causes problems.

Good luck

Last edited by Moparteacher; 02/22/09 02:28 AM.