The most common Mods are of course, Exhaust, Pullies, Gears, MAF, Chip etc.. Not all in that order, but those are the most common. Don't be fooled by the adds in the mags with there: ADDS 20 - 30 HP ! ! That is a bunch of bull. Read the FAQ and the forum and take it slow and easy. Ask lots of GOOD questions that arn't on the FAQ and you will learn a lot. DO NOT get the chrome cold air kit unless you only want looks. You will not get 20HP out of it and will mess with any upgrade like MAF, TB, Supercharger etc.. Stick with the advice of the board and it's knowledgable members.
Welcome aboard!
