If it had worked out twenty years earlier it might have been a thought.
Small two-stroke diesels are practically illegal - emission problem. Also, they don't do
more mpg, because the breathing is less efficient than a four-stroke. But where they might score is in an aero engine. They're less weight for power output.
BTW, if anyone wants to help with this project, not financially, but as a pair of hands, or getting components, I'd be happy to hear from him.
What I need most, is a small dynomometer.
Malc