I figured that 10hp would be an outrageous gain from such a simple modification as replacing the air filter. What other restriction are you mentioning that I may want to remove in order to get around 8hp from this? I ordered a set of underdrive pulleys, my Bassani X-pipe came in the mail Saturday, and I getting a Magnaflow Cat-back system. Aside from that, a throttle body/mass air meter (possiblitly), and a sport chip are on the way. I'm trying to let my engine breath as much as possible w/out hindering it's drivability. I'd like to get about 320+hp from all my total mods.