This Angular Momentum Engine in this patent application uses three simple systems: angular momentum, centripetal force, and relative motion to convert a rotational centripetal force to a linear centripetal force. This Angular Momentum Engine is an ‘add-on’ to any existing vehicles propulsion system. Centripetal force cannot accelerate a vehicle as once this centripetal force reaches a vehicles ‘net force resistance’, the resistance of a physical object to any change in velocity, the centripetal force becomes tangential. This Angular Momentum Engine centripetal force can only equal a vehicles ‘ ’ net force resistance, therefore acceleration is left to the exiting propulsion system, such as a series or parallel automotive hybrid systems, as an example. Centripetal forces are exponential, as its force is proportional to the square of the speed, while acceleration forces are linear giving this patent design an exponential edge over existing propulsion systems.