Chase99

Own a 2012 zr1 with the second set of cats and I have installed a B&B Fusion cat back exhaust and have the following questions....
- Can I remove the second set of cats and put on an x-pipe without the car throwing a code
- will removing them lean the car out enough to need a tune
- if removed the cats are will the car pass my state emissions test

Thanks for all answers

OBSSSD

yes
no
yes


Cheers!

911/Q45

Depends on your state and how knowledgable your inspector is. In CA any removal of emissions equipment will fail you.

Chase99

What manufacture makes an x pipe replacement for the 2012 and up models? i aasume the length and/or the flanges could be an issue?

Thanks

OBSSSD

You need a 2009-11 set of ZR1 cats with center section to install with your existing stock manifolds. Call John at 21st Century Musclecars at 972-417-7177 and I bet he has a set he could make you a deal on.

You will not have any emissions issues just be like the older year cars which pass just fine.

BenDiem

^^^ OP,

If you don't mind me asking, I'm curious, did you have any fitment issues with installing the catback? I'm considering an aftermarket catback myself.

Are you not happy with the sound of the catback, and is that why you are looking to add an x-pipe?

BTW, I could have sworn, the '12 & '13 Z06/ZR1s have an x-pipe...

Tks/Cheers,

B

OBSSSD

They do, but with a second set of cats in the center section

ZR1Cat

If this is correct, then why did GM add this second set of cats on the 2012-13s? Did the change in 2012 just affect the ZR1s or also the ZO6s, etc?

OBSSSD

All the cars got extra cats...

base car, GS, Z06, and ZR1

If it was actually an issue then what are people with 2009-11 ZR1's doing now to pass? There has never been a single poster that said they failed emissions visual or otherwise with the old setup on here - because it has never happened. Do you really think an inspection station would know this distinction?

There will be no issues but if you are that scared better not to modify your car at all

911/Q45

That may be true in TX, but they would know in CA. What state is the OP from?

ZR1Cat

You may not have understood my post. I am not planning to modify my exhaust. I am just wondering why GM added an extra set of cats to a system (2009-11) that apparently was working well to being with. Why add the extra cost of the cats to a supposedly well designed existing system? What was GM trying to accomplish with the additional cats?

OBSSSD

So then what are all the people with 2009-2011 ZR1's that live in California doing? Guess letting their cats rot in the garage

mirage2991

my guess is that emissions were scheduled to go up in 2012, and perhaps that was the only way to "improve" the system

911/Q45

Those of us with 2009-2011 ZR1s comply with our stock setup as installed, if you have a 2012 and remove the added cats you don't comply and would fail the inspection and be denied license renewal. I don't understand what you are saying.

OBSSSD

There are thousands of C6 owners who have headers with hi-flow cats in California that pass inspection every year - yet you think some dufus at an inspection station is going to know the difference between the 2011 and 2012 factory exhaust setup?

LMAO

Streetk14

Sorry for resurrecting an old thread, but it was left open-ended with some pretty bad information.

1) Government emissions standards changed right around the 2012 model year. GM added additional catalytic converters in the X-pipes of ALL C6 models for this reason.

2) a 2012 or 2013 car isn't going to need a smog check for at least 6 years. Really not something to worry about.

3) No smog station tech is going to notice that the car doesn't have the rear cats. Unless you're a C6 guru, it's not something you'd even think about. My 2013 doesn't have an emissions diagram under the hood, so I'd find it REALLY unlikely to ever pose an issue. On top of that, cars aren't even put in the air during a standard smog check.

4) The "sniffer" is now dead and gone for newer cars in CA. Even one less reason to worry about messing with the 2012+ X-pipe.