Quote:
Originally Posted by SemtexGT
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  |
There are catted "sports" downpipes for N55 and B58 which are ECE approved (legal with in EU zone). In fact I have ECE compliant downpipe from akrapovic in my 2017 440i. The G20 version is yet to be released. The problem is that new cars have also OPFs and not only cats here in EU. The OPF is actually located after the cat around midpipe. OPF is restricting exhaust flow atleast as much as cat is. To remain emissions compliant in Europe you need to have OPF in place for B58's produced after July 2018.
I really hope akrapovic does create ECE approved full exhaust system including downpipe and OPF for M340i. I'm sure this will be super expensive though...