Wait one second. Do you even understand CLEO? I mean you're asking like you almost know nothing about it! You should know that you can create velocity for cars with an simple opcode:
07D5: set_car 0@ velocity_in_direction_XYZ 9@ 10@ 0.0 rotation_velocitiesXY 0.0 0.0 unk 0.0
So whats up with you?