1. Really good write up on performance upgrades and which ones make sense. Apparently any cold air intake which leaves the filter visible is crap. And the only ones that will possibly give performance cost more then a grand.
http://forums.m3cutters.co.uk/showthread.php?t=6436
2. Apparently the oil used in the K&N stock airbox filter can cause the MassAirFlow meter to fail. So much for that.
Cost of parts was less then $80.
Shipped From NoCal Warehouse | Fuel Filter, M3 (2001-06), Each | 1 | $29.25 | $29.25 | |
Shipped From NoCal Warehouse | Air Filter, E46 323i/Ci, 325i/Ci M56, 328i/Ci, M3, Each | 2 | $12.25 | $24.50 | |
Shipped From NoCal Warehouse | Activated Carbon Microfilter, BMW E46 3 Series, All (1999-04), Each | 1 | $22.25 | $22.25 |