A simple script that is able to control a 2D car.
Using 2D wheeljoints and motors and physics 2D materials is possible to adjust stuff like:
-Aceleration
-Maximum Speed going Forwards
-Maximum Speed going Backwards
-Car's Mass
-Wheels Bounciness & Friction
-Back / Front / Both Wheel Drive
-Car's Rotation
To do this, all you need is a car, 2 wheels and 2 wheeljoints, then just slap the script on it and you are good to go! A car with alot of physical customization is all yours.