[unkiedave]

dont have an i4 but this should work just as it did for my v6. imo you've forgot 2 important upgrades. bored tb ( i think you i4 people have one for your car ) and a lighter fly wheel. this is what i would do. spend to 70 bucks for a good cold and and spend 25 bucks on a use throtle body that fits ur car and pay the 80 bucks for the bore and new butterfly plate. if you can find one that has been pre bored then even better. after the cai and bored tb pick up a used borla setup for about 250 -300. worth ever penny. then at your first excuse to get in that tranny buy and install a mx3 flywheel. the weight savings will kick up your acceleration. i have a 9lb fidanza flywheel and think it may be alittle rough for dd. the money you save on an used mx3 flywheel over the 9lb fidanza you can put towards a set of headers. with all these go mods you should probally upgrade your stopping with a nice set of brembo cross drilled rotors. that imo is the best bang for the buck.

70 cai
125 bore tb
275 used borla catback
50 used mx3 13lb flywheel
$520