hi all thought you might be interested in this little part I imported from the states for anyone with BF models onwards who are thinking of removing there cats - I did and got the dreaded CEL, spaced out O2 worked but this works a treat - no cel light for the last few months and a straight thru exhaust with no cats - ye ha.

heres the link for the mini-cat - you simply screw your rear o2 sensor into it and the whole thing screws into a 18mm threaded bung welded in your pipe somewhere or existing factory pipe like i did.

http://boost-controller.com/

or google Innovative performance & customs.

cost me nz $58 all up to import from the states to nz and was here in about a week or so.

Unfortunately over here its ilegal to remove or gut out a cat. Still a good idea to share around though.