California Emissions

[InspireSiR]

Does anyone know if the secondary cats are required in order to pass emissions testing in California? I will be keeping the primary cats on for sure, but if I can get away (pass emissions) without having the secondaries, I'll be a happy camper.

I checked the sticky: "Performance Mods / State Inspections / Reference Thread", but there were no replies for California.

Thanks!

[henryyxyu]

You might not be able to pass the visual portion of the smog check, but you should be able to pass the smog check itself though (if that makes any sense).

EDIT: Are you trying to take off the cats to make the exhaust louder? If so, its not going to make a drastic difference (IMO, haven't tried it yet on the M3 but from past experience). Your better off just getting an x-pipe, then swapping on the stock x-pipe when smog comes along. You'll gain a better exhaust note plus a few extra ponies. Just my 2 cents

[Finnegan]

Originally Posted by henryyxyu

You might not be able to pass the visual portion of the smog check, but you should be able to pass the smog check itself though (if that makes any sense).

EDIT: Are you trying to take off the cats to make the exhaust louder? If so, its not going to make a drastic difference (IMO, haven't tried it yet on the M3 but from past experience). Your better off just getting an x-pipe, then swapping on the stock x-pipe when smog comes along. You'll gain a better exhaust note plus a few extra ponies. Just my 2 cents

+1

[iTz oN!!!]

You don't need to remove the X-pipe for smog. As long as you dont remove the cats up front and you dont have CEL you are good. The resonator won't effect smog.

[InspireSiR]

This is exactly what I was thinking of doing. I wanted to swap out the stock x-pipe which currently has the secondary cats and resonators.

Are there any O2 sensors on the secondary cats that would throw a CEL?

Originally Posted by henryyxyu

You might not be able to pass the visual portion of the smog check, but you should be able to pass the smog check itself though (if that makes any sense).

EDIT: Are you trying to take off the cats to make the exhaust louder? If so, its not going to make a drastic difference (IMO, haven't tried it yet on the M3 but from past experience). Your better off just getting an x-pipe, then swapping on the stock x-pipe when smog comes along. You'll gain a better exhaust note plus a few extra ponies. Just my 2 cents