I have a little bit of a scientific background and would like to theorize if I could....
What about making a car engine where the engine is the secondary force involved, and the transmission is more the driving force, for the sake of energy efficiency?
I'm talking about using the principle of impulse momentum (ie the minimum force required to get an object moving), to charge hydraulics or whatever else, on startup, and then the transmission slowly releases such stored energy.
Think about this: a car powered by a bank of lawnmower pistons (bear with me here) that are there merely to work the hydraulics to charge the smart-transmission? Is this a workable idea?