Less restriction in the exhaust is always a good thing.
I'm not sure how restrictive the standard cat is though, anybody know in terms of ''cell'' rating?
I've read somewhere that on an NA car, a high quality sports cat is actually more benificial than a decat. Something to do with decats (generally) giving more BHP on NA cars at the expense of lower torque. NA cars do benifi from some degree of back pressure unlike forced induction cars which need hardly any at all.
This is also how i feel. Did ask TDF what their opinion was on the subject before the car got its mapping done and they just said that the actual catalyst in the 197 system is pretty free flowing as standard and shouldnt see any difference.
Aye, by all accounts the pre-cat is what strangles it.
You should have heard my old Golf's exhaust Woody, you'd have loved it... 3" decat and nothing but a backbox. The bangs on DSG changes were epic, proper rally slag style!!
look at jms automotives 197 developement thread. They cut the box out and extend the pipe. Theres a german site called richhard motorsport that sell y shaped pipe that weld in place of the cat. Some one on here got his exhaust mate to alter the manifold himself.