I used to have a 335i. Long story short I no longer have it and I'm a new member of 5post. I recently got the 550i but I don't know what parts to mod since I'm new to the 550i. My previous setup with my 335i was Riss racing DPs JB2R, Juicebox intake. I googled for cai and found these:
http://www.autopartswarehouse.com/sh.../bmw/550i.html
But I'm not sure if they're renown. Any more engine mods?