First, don't let them have a chance to chase - by keeping this dog in a fenced yard or on a tethered rope.
Now, what can be done to stop a veteran car chaser? One trick is to have a friend drive by in a car that the dog doesn't recognize, when the dog begins to chase, have the friend stop and spray the dog with a water gun. Repeat this routine with different cars until the dog gives up chasing or you run out of cars. Any dog that chases cars will be injured - the question is when and how badly.