As for gains, if all you do is an intake or filter upgrade you won't liekly see much as far as gains go. But if you combine that with some exhaust mods, you will see more gains.

If you allow it to inhale better, it must exhale better to make any improvement.

1999 Mystique LS V6 Alpine CDA-9807, Rear deck sub, Opt. TB, K&N RU-3530/MAF adaptor, custom heatshield, FSVT 17's, SCT 4-program chip, Eibach's/ST200's, Hella Fogs...