California Law BS: Straigh pipe to non NPP review
01-13-2019, 05:01 PM
#1
Heel & Toe
Thread Starter
Member Since: Nov 2018
Location: Socal..
Posts: 21
Likes: 0
Received 0 Likes
on
0 Posts
California Law BS: Straigh pipe to non NPP review
I have a 2007 LS2, cams, long tube headers, 3" catless exhaust with an X-pipe mated to 18" long Magnaflow resonators to 4" dual tips. No doubt it was loud, at idle, at every rpm band! It was nearly impossible to drive the C6 quiet unless I kept it under 2k rpm cruising....From a stop light, I would shift from 1st to 3rd.....rdiculous BS. going uphill and acceleratoring, nearly impossible to do so quietly with load. After sifting the forum for threads on stock base non-NPP mufflers, i read that folks with my setup including the non-NPP made a good exhaust note....BS. I swapped out my resonator/muffler to a stock non-npp muffler, IT IS DEAD QUIET. The LS2 makes more noise than the complete exhaust does now. Those of you Cali heads that needs a quiet setup, this is for you. I literally blasted by 2 PD's today. It was a sad, but,disappointingly quiet day. Lol!1 Think I need a Z06 NPP muffler soon....in themeanwhile, I'll enjoy the silence. @Antigravityone
Last edited by johnodrake; 01-25-2019 at 11:53 AM.
01-14-2019, 12:42 AM
#2
Safety Car
Member Since: Jan 2006
Location: Miami FL
Posts: 4,598
Received 69 Likes
on
45 Posts
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
My 2006 convertible with the stock non-npp mufflers was so quiet I could not shift by ear!! So I agree with the OP, if you NEED quiet, that is the way to go. Here in Florida we are not as **** as the Cali politicians and police, so my modified B&B dual-mode system suits my needs just fine.
01-14-2019, 01:23 PM
#3
Pro
Interesting... so you live in Southern California and drive a 2007 Corvette with significant exhaust mods. How do you get around the emissions test? Long tube headers on a 2007 is an automatic fail from what I have been told. Even aftermarket mufflers have been known to cause a fail at the emissions station. What's the trick in getting around the regulations over there?
01-14-2019, 01:37 PM
#4
Melting Slicks
Interesting... so you live in Southern California and drive a 2007 Corvette with significant exhaust mods. How do you get around the emissions test? Long tube headers on a 2007 is an automatic fail from what I have been told. Even aftermarket mufflers have been known to cause a fail at the emissions station. What's the trick in getting around the regulations over there?
01-14-2019, 02:01 PM
#5
Pro
I agree they should not, but a friend of mine in Long Beach claims his mufflers caused a fail because they were too loud. Not a smog issue, but apparently they check for noise levels too?
Another reason not to live in the PRC. :-)
Another reason not to live in the PRC. :-)
01-14-2019, 02:12 PM
#6
Melting Slicks
01-14-2019, 03:43 PM
#7
If your mufflers are louder than 95db @idle when measured at 20" back from the muffler tip (no more than 8" above ground) and at a 45* angle from the tips, then yes, you will not pass a state ref.
California's required bi-annual smog tests do not check noise level, if I'm not mistaken. Only when you get a state ref ticket or get pulled over for loud exhaust.
California's required bi-annual smog tests do not check noise level, if I'm not mistaken. Only when you get a state ref ticket or get pulled over for loud exhaust.
01-14-2019, 04:02 PM
#8
Race Director
Member Since: Apr 2016
Location: Pittsburgh
Posts: 10,679
Received 4,713 Likes
on
2,998 Posts
2023 C6 of the Year Finalist - Unmodified
2022 C6 of the Year Finalist - Unmodified
2021 C6 of the Year Finalist - Unmodified
OP, How do you get past a smog test with headers in Cali?
01-14-2019, 05:30 PM
#9
Heel & Toe
Thread Starter
Member Since: Nov 2018
Location: Socal..
Posts: 21
Likes: 0
Received 0 Likes
on
0 Posts
..
I have friends that owns smog facilities...It's the only way around it.
Interesting... so you live in Southern California and drive a 2007 Corvette with significant exhaust mods. How do you get around the emissions test? Long tube headers on a 2007 is an automatic fail from what I have been told. Even aftermarket mufflers have been known to cause a fail at the emissions station. What's the trick in getting around the regulations over there?
01-14-2019, 05:34 PM
#10
Heel & Toe
Thread Starter
Member Since: Nov 2018
Location: Socal..
Posts: 21
Likes: 0
Received 0 Likes
on
0 Posts
..
Interesting... so you live in Southern California and drive a 2007 Corvette with significant exhaust mods. How do you get around the emissions test? Long tube headers on a 2007 is an automatic fail from what I have been told. Even aftermarket mufflers have been known to cause a fail at the emissions station. What's the trick in getting around the regulations over there?
01-14-2019, 05:36 PM
#11
Heel & Toe
Thread Starter
Member Since: Nov 2018
Location: Socal..
Posts: 21
Likes: 0
Received 0 Likes
on
0 Posts
...
This is nonsense. However, at certain smog stations, any modifications done to your exhaust system, they won't even test you and send ya on your way...
01-14-2019, 05:49 PM
#13
01-14-2019, 06:30 PM
#14
Safety Car
Here in Michigan we can only drive our cars 7 months out of the year, but we have good 93 octane, no smog, no engine or exhaust restrictions.
Dont know how you can stand the pile of stupid laws out there.
Dont know how you can stand the pile of stupid laws out there.
01-24-2019, 10:11 PM
#16
Melting Slicks
Member Since: Oct 2015
Location: Mead Wash
Posts: 3,300
Received 766 Likes
on
538 Posts
2020 C6 of the Year Finalist - Modified
C6 of Year Finalist (appearance mods) 2019
Exhaust
Interesting... so you live in Southern California and drive a 2007 Corvette with significant exhaust mods. How do you get around the emissions test? Long tube headers on a 2007 is an automatic fail from what I have been told. Even aftermarket mufflers have been known to cause a fail at the emissions station. What's the trick in getting around the regulations over there?
The following users liked this post:
Welker1 (01-25-2019)
01-24-2019, 11:26 PM
#18
Melting Slicks