Louder sound while passing smog (CA)
Thread Starter
Heel & Toe
Joined: Oct 2018
Posts: 18
Likes: 1
Louder sound while passing smog (CA)
Hi all, I'm coming up on 1 year of ownership and already wanting a louder sound. I've been doing some research but I still have some questions.
Basically I'm looking for a better and louder sound without droning, breaking the bank, keeping NPP, and failing smog. I'm in California so we have the strictest smog testing. I also don't really want to modify my car again and again every time I have to get smog checked.
My research has lead me these options. Does this look correct to you guys?
1. Install X-Pipe - Most likely will not pass California smog
2. Install a Catback exhaust system (with no X-Pipe) - Will pass smog but expensive but will give marginal returns when not paired with X-Pipe(?)
3. Replace only the mufflers - Is this even possible? I don't see any companies selling a muffler-only replacement, but this would give me the louder sound while being within my requirements.
I don't really want to drop almost two grand on a new exhaust system if I can't reap the benefits since I'm not going to install an X-Pipe.
Basically I'm looking for a better and louder sound without droning, breaking the bank, keeping NPP, and failing smog. I'm in California so we have the strictest smog testing. I also don't really want to modify my car again and again every time I have to get smog checked.
My research has lead me these options. Does this look correct to you guys?
1. Install X-Pipe - Most likely will not pass California smog
2. Install a Catback exhaust system (with no X-Pipe) - Will pass smog but expensive but will give marginal returns when not paired with X-Pipe(?)
3. Replace only the mufflers - Is this even possible? I don't see any companies selling a muffler-only replacement, but this would give me the louder sound while being within my requirements.
I don't really want to drop almost two grand on a new exhaust system if I can't reap the benefits since I'm not going to install an X-Pipe.
Last edited by CalMotion; Dec 12, 2019 at 01:05 PM.
Drifting
Joined: Sep 2017
Posts: 1,464
Likes: 771
From: Miami
C7 of Year Finalist (performance mods) 2019
Ping vendor @NORCAL-SS for advice here. He's a great resource in CA.
The tunnel plate completely covers the X Pipe so the change won't be seen.
I believe that that the two rear cats are not monitored by the car's computer.
If you fail smog, put the OEM xpipe back on. It's easy if you can turn a wrench and have the room to do so.
The tunnel plate completely covers the X Pipe so the change won't be seen.
I believe that that the two rear cats are not monitored by the car's computer.
If you fail smog, put the OEM xpipe back on. It's easy if you can turn a wrench and have the room to do so.
Last edited by DTOM; Dec 11, 2019 at 06:49 PM.
Thread Starter
Heel & Toe
Joined: Oct 2018
Posts: 18
Likes: 1
Would putting their exhaust system on without X-Pipe provide little improvement?
Last edited by CalMotion; Dec 12, 2019 at 01:07 PM.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
cats need to stay on....mufflers wont fail your smog but beware of the new sound laws. Stupid huge fines
Adding an x pipe wont do anything, in fact cat backs rarely do anything other than sound. Id fool with muffs thats about it.
Adding an x pipe wont do anything, in fact cat backs rarely do anything other than sound. Id fool with muffs thats about it.
Instructor
Joined: Mar 2009
Posts: 237
Likes: 78
From: San Diego CA
Thread Starter
Heel & Toe
Joined: Oct 2018
Posts: 18
Likes: 1
Thanks, look like I'm just going to have to fork out $2k for a NPP exhaust system
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Melting Slicks
Joined: Aug 2016
Posts: 2,762
Likes: 1,017
From: MOUNTAIN HOME Arkansas
Possibly electrically operated “cutouts” in OE exhaust system? Not positive that would give sound you want without drone. Research on Google & if it might work for you then research here also.