I had read a posting about easy E46 performance upgrades a couple of months ago but can't find it now! Anyway, thanks to the guy that posted it whomever it was. I've got a 2004 328 and got the model E46-A1 Signature Motoring heat shield and the K&N filter for about $170 total (signaturemotoring.com). I’ve heard from those that dyno-tested that the HP gain is only about 9-12HP, but the power increase is very noticeable and the sound is not any louder except and high RPMs where it howls! Very cool. Whole setup installed in about an hour (but I've got two left hands and take a cold beer after every half hour working).
Anyone have a good bead on some replacement rims? I'm looking for something quality but just can't spring for OEM.