How to increase MPG (w/ aftermarket parts)?
hey guys. does anyone know how to increase mpg? and i don't mean a different driving style, i mean like aftermarket parts. I have a 08 G37 coupe. My mileage isn't toooooo great, but its not that bad. i saw something like a computer chip or something like that which might be able to increase mpg but i'm not sure what the deal with that is. Anybody using something like that? Recommendations?