Is cost an issue?
You mentioned MPG and the first thing that came to mind was fuel injection. I seem to remember some discussion about do-it-yourself EFI kits a while back, and that will help both power and MPG.
I think there's even a "build-it-yourself" kit if you're good at electronics, called
Megasquirt . You buy the kit and the software to tune it, and can customize for your application. Search th
Beyond that: headers, exhaust, port & polish, high torque cam grind, etc. etc. etc...
-Boyo
