Well if you have 2 turbos lying around you could go one step better - A rocket engine (beats the crap out of a turbofan in terms of grunt). Set up both turbos to spin with compressed air. Use one to compress lpg, the other to compress either air or O2. Inject both compressed gas streams into a combustion chamber and spark it up. Your very own turbopumped rocket engine. On a real system the combustion chamber wall is gas cooled and the coolant is recirculated to drive the turbopumps...NRB said:I was thinking the same thing - I've got 2 sitting in a box in the garage. I still don't fully appreciate how it works, especially how one would mount it.