I am a college student and my main concern is getting the most of the my money. My dad drives a 1999 Corvette with a 422ci, supercharged engine, and it puts out roughly 750rwhp (sometimes he gets lucky and it has seen up to 777rwhp, or as low as 680rwhp). So...it must get horrible gas mileage, right? Wrong! If he puts it in 6th gear and drives about 63mph (1300rpm I think...he has different gears), he gets about 35-37mpg!! The car is really aerodynamic, and that sixth gear is meant for cruising in style and on a budget. I figure there is a lot more to it though...tuning probably plays a large role in the whole phenomena.

Here is my question: what kind of modifications on a 2.2L non-ecotec would increase gas mileage? Or better yet, even though this may already be a thread, what is your average economy? I believe this belongs in the performance forum because performance is about getting the most of your car. My view just differs in that I want a car to go the distance on as little gas as possible. (No, I don't want an import brand, I like my GMs).

My current theory is that making the engine more efficient would not only produce more power, but better economy. I'm not trying to sound elementary, but maybe starting with the exhaust...header...head...stuff like that. These things don't affect how much gas is actually dumped into the system, do they?

I have read through a thread that talks about getting the best gas mileage, but my question is more about modded cars getting better than stock economy.

Regards,
Jordan

On a side note, as a comparison, the car I drive right now (my dad's work car) is similar in setup to his Vette. It is a 1998 WS6 Trans Am with an LS1 stroked to 383ci, also supercharged. I would love to keep driving this, but the gas mileage is horrible for my area (about 7-8mpg city, about 18 highway). Sixth gear is pretty tall...at 70mph the engine runs at about 2000rpm. I baby this thing to get the best gas mileage I can, but I never see more than 18. (it is a TON of fun though...it dynoed at 550rwhp...sounds like a monster:-)