yes, that's quite difficult using the command objects, because you need to control the car in every second depending on it's actual behavior. You can do it with a game controller and DirectControl, if you're working on Windows. You can then drive the car like in a game.
It helps, reducing the grip and increasing the torque of the car. And moving the center of gravity to the front by moving the engine to the front.
I'm thinking about a coffee script that controls the throttle depending on the current steering. I'll come back then.