Propulsive is the adjective for that forward push. A propulsive force is a force that drives a vehicle on. A rocket engine is propulsive: its job is to shove the rocket forward. You can also call a system or a design propulsive when it is built to make that drive. The word stays in technical and formal English — science, engineering, sometimes careful sports writing. Everyday speakers almost never use it; they would just say “it pushes the car forward.” Though actually, writers sometimes stretch it. A “propulsive story” or a “propulsive beat” means the writing or the music keeps pushing you on, and will not let you stop. That use is not about vehicles, but it still keeps the idea of a strong drive forward.