I am looking at replacing my exhaust with the NM Engineering Downpipe-back exhaust (https://nm-eng.com/collections/mini-...ystem-nm308844).

My question is, will replacing my stock exhaust with this effect emissions? I live in Northern Va where they have emissions testing and I don't want to install this and find out later my car is failing the tests.

 

If it helps, I installed an aftermarket cat-less downpipe and a high flow 200cell cat and I just failed.
I'm pretty much screwed, so be careful and do your research before going all in like I did.

 

I have the NM Engineering downpipe-back exhaust. What is removed is a secondary (or even tertiary) cat as well as the stock resonator. A different resonator replaces the stock one. There are NO OXYGEN sensors affected, so, unless they look, they will not be able to tell it isn't stock. Oh, well, they can probably hear it isn't stock, if they know what a stock Mini sounds like. There should be NO REASON to have codes pop up in the OBDII system that they read. My GUESS is that you'll be fine as far as codes or even a tailpipe sniffer can detect.

Love the sound and looks of the NM Engineering downpipe-back exhaust. If you get it, let me know, I have one tip to give you to make it easier to mount.

 

Where I live they have these RAPID emissions testers on the side of roadways. You drive by one and it does the test and mails you the results.

I want to be sure the car will pass those tests. Don't care much for a visual check.

 

I would think you'd be fine if it's just a sniff test!