CARB/Smog and Good-win midpipe

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TimS316
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Joined: Wed May 08, 2013 9:20 am
Location: Carmel Valley Village

CARB/Smog and Good-win midpipe

Post by TimS316 »

I installed a Roadster Q exhaust a year ago on my 2011SE. I recently bought it off lease, and as a result, it needed to be smogged. Passed the test no problem. I originally had hoped for a boost in sound with the muffler which I got, but not to the level my brother's 06 from Oregon has with the mid pipe and earlier roadster model exhaust.

Since I own it now, and have just gotten through smog, I spoke to muffler shop about replacing the mid pipe. He said he thought it would be fine, and wouldn't be a smog issue since measurement takes place in front of the system. My reading of the CARB smog changes suggests to me that changing out the mid pipe should not be a problem smog or pollutant wise even if its not 'approved'.

My questions at this point are:

1. Am I likely to have smog issues in the future if I make this move to the mid pipe?
2. Am I likely to achieve the increased sound values by making the change?

I know sound is subjective, but there is a clearly 'deeper' exhaust note throughout the engine range with my brother's car than with mine.

Thanks for your help.
Brian
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Re: CARB/Smog and Good-win midpipe

Post by Brian »

Just so you know, technically, the CARB numbers must be on any replacement midpipe or you can fail the smog. We will eventually do special CARB version of our midpipe for all 2006-2014....but that won't happen until NC out of production.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
TimS316
Posts: 2
Joined: Wed May 08, 2013 9:20 am
Location: Carmel Valley Village

Re: CARB/Smog and Good-win midpipe

Post by TimS316 »

Thanks, Brian. Appreciate the heads up. Do you think most smog shops even look under the car? I've never known one to do so.

On the sound question, which of the two mid pipes you're offering would give me the best boost if I decided to take my chances on the smog issue. At the very worst, I could have the original bolted back up if necessary. I'm guessing I'd be good on smog for at least 4 years from now, having just had it smoked in April with the 'sale'.
Brian
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Re: CARB/Smog and Good-win midpipe

Post by Brian »

Both our midpipes are 2.5 inch all the way through, doubt you could find much or any difference between them on the dyno.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
Freescopesdad
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Joined: Thu Feb 23, 2012 9:42 pm

Re: CARB/Smog and Good-win midpipe

Post by Freescopesdad »

Tim, I added the GWR midpipe to my 2012 about 18 months ago, when I gfelt that the RSII muffler did not add the amount of sound that I was looking for. I was also looking for a little midrange torque boost as well. Even with the midpipe and muffler, the sound was not as loud as I wanted [needed :) ] so I have since performed a mufflerectomy and had a local shop weld up a Y-pipe and twin chrome tips in the rear. My car is now loud [to my liking].

As to the smog issue, California is [still] doing the tailpipe test, and who knows when they will finally convert to the OBDII-based testing, if ever. As such, the midpipe will impact the actual emissions, but by how much I couldn't say. Although the cat in the midpipe is no doubt effective, it is not OEM nor CARB approved. Emissions may be higher, but still pass. I guess I will find out in another 4 years.
Ron Petrich
http://www.sacramentoareamiata.org
2016 ND GT 6MT|ZII/NT01|Ohlins|Progress|OFT|HDDDM4
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