[samwichse]

Originally Posted by ConnClark

If you want something that is considered thinking out of the box try a rotary Atkinson cycle engine. It has thermodynamics working in its favor.

File:WikiDartEngine.gif - Wikipedia, the free encyclopedia

I don't know, that thing looks pretty thermodynamically terrible. The combustion chamber design has a relatively huge surface area to volume ratio and there's friction points all over the place. Seems like a while lot of work to achieve what a plain old turbo can accomplish.