I've never understood these "high flow cats". Are they able to pass emissions standards at MOTs? If not, what is their purpose over a catless downpipe?
I'm in the process of getting an M340i and I see the forums exploding here about downpipes but I couldn't, with good conscience, drive the car on public roads without a cat, I'd be too paranoid all the time. (I live in Europe, so things are much stricter about exhausts here)
Could someone enlighten me on this, would be much appreciated
