Toll Free, I'm glad you brought up alternative engines and diesel. I have a great idea for a two stroke diesel, I just don't have a donor car to put the idea into practice. It would use a Mercedes or VW diesel and would not be inefficient because diesels squirt the fuel in after they compress the air (after the valves have closed). I don't know about a rotary diesel, though. I don't think they have the compression to do it properly. They don't have valves that close so that a lot of pressure can build, but mabey some very massive turbos could do the job so long as there is not too much overlap between the exhaust and intake ports.