The Ultimate Guide to Suspension and Handling – Bump Steer/Toe Steer

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Another example for toe curve correction by bushing is this toe steer eliminator kit for an EVO, made by Whiteline. This corrects the toe curve in a lowered EVO.

This is the kit in place on an EVO IX.  It relocates the pivot point by about half an inch.

In Pro Drift cars toe rod pickup points are often relocated to give the cars more toe in under roll.  This way the toe steer can help the driver step on the gas harder while drifting to get more speed and throttle commitment while sideways while running less static toe.  This gives more predictable handling off throttle so the car will have less of a tendency to straighten up and shoot in the wrong direction.

Whiteline has offset bushings for the EVO that relocate the pivot points to reduce toe steer and its a simple matter to have a racecar fabricator reposition trailing arms and other links to correct their geometry on highly lowered cars.  Take a walk through the pits at a World Challenge race and you can see much of this in action.  It isn’t too complicated or expensive.  Semi trailing arm cars toe out when lowered.  It’s a common trick in the 510 scene to slot the mounting points on the crossmembers to correct the toe, camber and the roll center by moving the rear mounting point out and up with the front mounting point going in and up.

You can also buy weld in universal pivot adjusters.  These make adjustments super easy and only require basic fabrication skill.

Here is an example of the adjusters welded to a Datsun 510 subframe where they are used to make rear toe and camber adjustable.  How do you make a semi trailing arm suspension car handle well? You add a lot of static toe in and make the suspension stiff to limit movement.  This strategy has worked for generations and a lot of races have been won with semi trailing arm equipped cars.  However nowadays with more sophisticated suspension designs becoming common in production car racing, semi trialing arm cars are not competitive anymore except in vintage and spec racing classes. 

So we have thoroughly explained the subjects of bump and toe steer and how to fix them.  Next in our series, we will continue to look into other geometric aspects of your car's chassis and how to improve things for performance use.

If you are new to the series, I suggest you look at and read the whole thing from the beginning.

The Ultimate Guide to Suspension and Handling