Originally Posted by Matt@Camber-Toe
This. Bmw is not going to entirely redesign something if they can help it. This helps the bean counters stay happy :-)
this also means someone could put the N55 exhaust on an N54 car...with no more secondary cats in the i models, it could be a cheap way to upgrade to a more free flowing factory exhaust.
Time to get a newbie with the N55 to get an exhaust