Previous work has shown power steering boost curves are uniquely determined given a vehicle and a single objective target. The objective target used was steering gain Sg vs. lateral acceleration ay where steering gain is defined as the slope of the torque vs. lateral acceleration relationship. The previous work is expanded and applied to real world steering systems. Specifically, methods are provided to analyze the nonlinear behavior of a steering system for two opposing cases. In the first case, both the vehicle and nonlinear objective steering performance targets are known; a method to compute the nonlinear boost curves to achieve the targets is provided. In the second case, the vehicle and steering boost curves are known; a method to compute the objective measures is provided. The objective targets can be in many forms: steering torque vs. steering angle, steering torque vs. lateral acceleration, and lateral acceleration vs. steering gain, etc. The equivalency of the targets is discussed and methods provided to convert between different objective targets. The influence of static friction on steering performance is derived. It is shown that the natural hysteresis of the steering system is due to a coupling between static friction and a vehicle parameter that is easily derived from the bicycle model. Test results are provided to validate predictions.