Actually Brennan, I don't believe ANYONE here REALLY knows...As long as I have been on the boards I visit....I have NEVER seen or heard of ANYONE taking their car to a dyno and doing a BEFORE AND AFTER run.....never......the data is just not there.....and all you can and will get out of the makers of these different intakes is their CLAIMS....no hard data....no dyno slips....so there ya go. All I know is that my car feels more responsive with my intake, and it sounds better too....as for HP gains? who knows. they are UP TO 8-12 HP....which means a big fat ZERO is also possible and still within the claims of the maker. THAT is why they say UP TO...it starts at 0.