If I was to get the chip....what would that do to gas mileage
Chips don't work, the only way to improve mileage or power is to buy a re-programmer ie Diablo, Superchips, Hypertech.
The chips normally just "lie" to the computer, telling it that the car is colder than actual or the throttle is depressed more or less. This usually leads to more fuel and timing making the car feel quicker. It normally hurts gas milage. In fact most chips cannot affect full throttle as the computer has "hard" settings for full throttle operation.
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