I will pay $30 and up for a mini rotary for a zip zap. I would also like to have a fuel tank and it has to make the car run at at least the equivalant of a 1.0 motor. I would like it to be faster though. I would like it fairly soon. It would also need to be fairly reliable. It would be best if it would be prefitted in the car. It would need a supply of fuel and I would need to know what fuel would be used. I will not be able to pay instantly. I would like the builder to build more than one. I would go up to maybe $75 per car but would like to keep it low cost. Hope someone can do it. You could also sell them as production but I would want a few engines to fit them in my bit-charg. I would also want them to have different performance qualities like high torque or high speed. I have attached a link to explain how a rotary engine works. Good luck!!!!!!!
http://www.howstuffworks.com/rotary-engine.htm