Join Date: Dec 2005
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It isn't illegal to run a post 1992 car without a cat,but you will most probably need one to get through an MOT,especially if your running a modified inlet system.
I must admit,I've never seen or heard of anyone being prosecuted due to a roadside check,but I suppose it does happen.
What I'd do to start with is remove the cat and have a replacement pipe made up,then take it for an emissions test to see how close you can get.If your somewhere near the limits,then I reckon you'd get away with running it on the road without a cat.The fast idle will probably be somewhere near anyway,it's on idle that I think you'll struggle.
I'd rather push my Alfa than drive a BMW....
Currently in Lagdti's garage:
2004 Saab 9-5 HOT Aero and a 2001 Audi A3 1.8 Turbo