I have the INJEN CAI, and it made a SIGNIFICANT difference in the 1st and 2nd Gears of the car (more torque)! How much? I do not know b/c I do not have the $200+ to have it hooked to a DYNO and confirm. However I will echo other comments that the CAI is just part of the overall objective. I plan to do other mods like exhaust, sparks, and I've already replaced the oil with RedLine 0w-20 w/ MOLY b/c I want to enjoy my "Zoom-Zoom" for many years to come. The $200 is a small price to pay for the added performance you get from the CAI.