steering help

[rip]

hey guys I'm working on a spread sheet that help calulate spacing and steering loss. I've got the spacer thing worked out and I think it's right but I steering part is well tougher.

I've been able to account for differences in angles with respect to a stock rim, but because how close the wheel is the center of the car also determines the radius of the turn its not complete.

Any one know the relation between the turn radius and the distance the wheel is from center of the car?

thanks