Did you continue to notice any butt dyno difference after the ECU had some time to learn, say after 500 miles? Most of the reports here and elsewhere say that, unless you want the sound, a CAI is a waste of $$ and will do more harm than good (they flow more mostly because they let more dirt through). It may worth the trouble if your production tolerances are on the margin. I think K&N filters are pretty well noted to be more snake oil now days than providing real gain. But your experience will vary.
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