[scrabblehack]

I was thinking that jet fuel had a higher heat of combustion than gasoline....

http://en.wikipedia.org/wiki/Fuel_efficiency

has regular gas at 125K BTU/gal,
aviation gas at 120.2K BTU/gal,
jet fuel slightly more, 127.5K-135K BTU/gal.

[Captain Shamrock]

Thanks, That adds to our “evidence”!