Originally posted by 91Teg
In theory it should help gas mileage. I'm not sure if it actually does though. Oh and keep the stock powerplant. If you wanna go drastic with the car turbo it.
It makes the engine run more efficiently, but not more fuel efficiently. There is a slight difference. When you bolt on the power adders, the engine flows more air. Since it is getting more air, it also takes more fuel to mix with that air. This means it will burn more gas, faster, but not too much so.