Quote Originally Posted by JohnL View Post
You’ve lost me here, I don’t follow what you’re trying to say (but, I suspect I might disagree if I understood you clearly…).
The effect is similar to that of a car in a cross-wind (i.e. an applied lateral force at the centre of gravity). Our example car is traveling down a flat road with a wind blowing from right to left.

The more understeer a chassis is, the more it will yaw to the left in the cross wind. An oversteer chassis will yaw to the right in the wind, and a neutral steer chassis will not yaw at all.

If you take an understeer chassis and instead apply a lateral force further towards the rear of the CG, it will yaw less than if the force was applied at the CG. If you go far back enough you will reach a point where you get zero yaw.

If you instead apply the force ahead of the CG, the chassis will yaw even more to the left than the first example. Go far enough forward that you are now at the front track and imagine that instead of the cross-wind applying a force, the front tyres do due to geometry changes under power application. The greater the car is understeer, the greater the yaw (felt as torque steer) from the tyre force.

If you modify your understeering FWD's suspension such that the rear track's slip angles are greater per unit of lateral acceleration, and the front track's slip angles are less per unit of lateral acceleration*, the point at which a side applied force gives zero yaw (the neutral steer point) is moved forward towards the CG. To get the same yaw to the left as the understeer example, you need to apply the force much further forwards towards the front of the vehicle - the same lateral tyre force at the front track results in less lateral acceleration and less yaw. Forces at the front track have a harder time upsetting the vehicle in this configuration.

Summary: The more understeer your chassis, the more torque steer.

I hope I've made myself more clear. Feel free to pick up my mistakes. Automotive dynamics is not my direct field of study, simply a hobby.

* There are many ways to do this. It is not impossible, or even difficult to produce a neutral steer chassis with a forward CG - this configuration does not have to mean perpetural understeer.