[Big Dave]

Dremd asked if I was serious. Serious as a heart attack, dude. It has already been done. See Post #15. This ol’ boy put a 6.5 NA diesel in a older ‘Vette. He even only was half-hearted about MPG because he stuck with the wasteful old TH400 automatic, but he still got 48 MPG.

I work with a guy with a C5 and talked him into running a tank doing some (reluctant) hypermiling. He has the LS1 engine and a T-56 and really just coasting to lights got him a thankful at 31 MPG. The old 6.5 ‘Vette automatic rig got well better than a 25% improvement over a six-speed gas-pig. Diesels are that much more efficient than gassers.

6.5s weigh about as much as a 454 and there are literally thousands of 454 ‘Vettes running around. A 6.5 takes up about the same space as a small-block, but you might have to remote-mount the turbo or batteries.

A diesel ‘Vette is a very doable project and will give you excellent MPG, but certainly do not think you’ll have the acceleration of an LS1.