I came across this fascinating article the other day about a guy who got 40_ mpg out of an old Jaguar.

The article is great: it goes into the engineering details of why his original Jaguar got such crap mileage, and all the steps that he took to overcome its deficient engineering.

I would love to hear from anyone here who knows the technology behind typical Honda Fits. In particular, how many of this guy's modifications could be applied to a Fit? Or, do most modern cars already incorporate the technology described by that guy?

 

Um, Honda already did that.

Electric power steering, check.
Strong, lightweight materials, check.

The cooling system isn't exactly oversized, but a new radiator and water pump wouldn't take away that much weight.
Ading intelligence to the AC compressor isn't on my List of Things To Do, but getting under the dash to disconnect the AC switch from the mode door dial is.

A lower grille block and a CR-Z belly pan would also be helpful.

But bone stock with the tires at max sidewall, the Fit can still turn in some really good numbers.