[///m_dL]

2015 BMW 428i AWD Gran Coupe M Sport. I'm thinking about getting a catted down pipe. I have a Frequency Intelligent exhaust installed. Any suggestions? Does it pass emission tests?

[mike@x-ph.com]

I recommend googling your state emission laws

[Eddien123]

I've heard it was hit or miss. If your state does a sniffer test it likely will not pass emissions. And in a lot of cases the car will still throw a code. I believe stock cats are something like 2 massive 400 cell catalysts. Where as the high flows has 1, 200 cell which the O2 sensors will read as a deficiency. In that case, you'll have to code off the check engine light and in that scenario you might as well have gone catless. I don't know how intensive the inspections are in your state so you'll have to figure that out on your own.