I've got the car driving around using HPWM to control the electronic speed control and the steering servo. This is a high quality hobby level car. It seems to not react quickly enough to the PIC commands. It was designed to have a person at the radio transmitter controlling with finger and wrist movements while watching how the car performs. This is a beautiful mechanism when human judgment is included.

A toy level car runs the wheels with direct current. The steering is a bang bang servo with a mechanical mechanism forcing it straight. Fritzl used a toy level car in his wall racer. http://letsmakerobots.com/node/696

I have added 'kickers' to the steering commands. Realizing that steering straight is the servo's action when given no current, I figured that transitioning from hard left or hard right to straight might be faster if the go straight HPWM command were preceded by a momentary hard shot to the opposite extreme. My first experiment did little to improve response.

Of course it might be that my car needs a grease job.

Hmmm....

Ken