For people with track pipes or removed cats.
http://forums.bimmerforums.com/forum/showthread.php?t=525568
http://www.k-series.com/forum/showthread.php?t=8833&highlight=sim
They also sell them on Ebay. I don't know if they work or not, just sharing info.
http://forums.bimmerforums.com/forum/showthread.php?t=525568
http://www.k-series.com/forum/showthread.php?t=8833&highlight=sim
They also sell them on Ebay. I don't know if they work or not, just sharing info.