Toe out front static alignment

[CHagen]

This is fairly common among auto crossers and some road racers to improve on center steering response for turn in at the expense of braking stability usually. I dont understand how toe OUT up front improves on center response, it seems counter intuative. Unless drag forces from inside tire are greater than i expect. Can anyone shed some insight?

 

[JackAction]

It doesn't. What is making your car more responsive is the addition of camber. But then you are stuck with a constant force pushing the wheels one against the other. This will be a problem in straight line stability as just a slight difference between left and right geometry - one wheel is in a different position (wrt to the body) than the other one - will just make your car wanders left and right.

To eliminate that problem, you add toe out to counter balance that camber force, hence no left and right wheels fighting one another in straight line.

But as soon as you start to turn the steering wheel, camber gain appears quickly, thus still improving your steering response.

 

[NormPeterson]

In autocrossing the turns are very tight relative to the car's track. Toe-out is a crude way of making the available Ackermann correction suit driving conditions that are far more enthusiastic than originally intended for the car at such turn radii. It also enhances turn-in (the flip side here being undue twitchiness in more normal driving).

Twitchiness is something that can be lived with during autocross where the car is at relatively low speed and hardly ever in "steady state". Not so nice at higher speed on a road course.


Norm

 

[patprimmer]

I would have thought twitchiness was actually an advantage in autocross

Regards
Pat
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[wiloberlies]

I think this topic has been touched upon recently, you might have a look at the thread entitled 'tire forces about CG'.
I think when the wheelbase length and track width are fairly to each other (square car), and given high steer angles, the longitudinal component of the steered wheel can create a yaw moment into the turn (inside wheel), while the same component of the outside wheel is stabilizing (out of the turn).