Ok so I JUST bought a 2004.5 S40 T5 and I have a few questions. Im going to buy the K & N air filter and I was wondering how to do the setup? The problem Im having is the big black box with what it looks like the cars main computer is mounted to. Once I go to install the K & N where would I remount the compter? If anyone has done a complete air filter swap please lend me a hand! Also anyone know a link for upgraded blow off valves? I'd alo like to put in a boost gauge (without "T'ing" it off and losing boost). One more, on both back doors by the door handles there are things that look like little speakers but no sound comes out of them. Have mine gone out or are they not speakers? Lol Thanks for any help and advise!