Looking at a used JCW exhaust system. The downstream cat is replaced with this system. Any problems?

 

No issues with losing the downstream cat on the MINI exhaust. It is not measured or probed by the engine.

If your state has extreme emissions testing, they might notice the cat should be there for your model year.

I would bet they don't take note or issue.

Now if you have a DP and this exhaust, you might have some need to put on your stock exhaust for emissions testing.

 

You won't have any problems as it is unmonitored and does not have any sensors in it like the downpipe cat. You might run into a problem if you state is a CARB state like California and some other states.

 

Thanks to my DS/B brothers for the replies.
No car inspections here in Kansas. Not even basics such as lights and turn signals. Cars here are mlostly delivered minus turn signals.

 

That is because of the big "FARM" painted on the side of most trucks