I'm on another forum debating the topic, and it's been quite a while since I've taken a physics course. Say, for whatever reason, the acceleration of gravity doubled. So now the vehicle would have twice the weight, but the same mass. How would that affect the acceleration of an automobile on a horizontal plane? I would think it would have to mean it would accelerate slower mainly due to increased friction, but there are others saying the increased weight would actually cause it to accelerate more quickly and corner better due to increased friction. It hasn't really been discussed, but wouldn't this double gravity also cause the motor to spin slower, and require more torque to spin the drive train, wheels, tires, etc? All of which would result in the vehicle accelerating slower than at normal gravity.