[ODE] Driving boxes on the arc or curve.

[Christoph Beyer]

I'm not realy good in english, maybe i don't understand your problem,
butt i will try to give you an idea.

maybe you could set linera and angular velocitys directly ( not with 
force and torque ).
With this, you will get a nice linear movement, if the car should stop, 
you have just to damp velocity.
Set the linear velocity in the direction, the car is currently orientated.
And if the driver turns his car, then set for this time a angular 
velocity too.
I hope i could help you ;-)

chris