Originally Posted by JakeZ34

well this is what he told me, if you just do an intake upgrade and everything else stock sure the Stillen and Injen will show 10-17 HP gains but once you decided to upgrade other things such as exhaust, headers and high flow, the intakes will not come in the factor of adding HP if not any. So he recommended to just get a K&N drop in filter. He is not K&N sales person nor is he a stillen / injen person as well. It's just his two cents and he's got data to back it up. But I don't want to give out names because I don't want people to flame.