Welcome to the boards! I think for most of the folks who did a CAI mod, the difference in mileage was pretty negligible. And if CAI is all you do, the difference in performance is pretty negligible as well. Most folks do a CAI in combo with an exhaust, but this is to bump the performance, not the mileage. I haven't heard of anything yet to increase mileage.

Well, except for keeping your foot out of it!
