02-02-2018, 05:21 AM | #15 |
Drives: 2017 Camaro 2SS / 2012 CBR1000RR Join Date: Jul 2017
Location: Louisville, KY
Posts: 97
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My understanding is the crimps are there as a deformable structure to protect upstream exhaust and engine in the case of a rear end collision. Power losses? I have no idea and not worried about it.
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02-02-2018, 07:25 AM | #16 | |
Drives: '17 ZL1 Join Date: Jul 2016
Location: Fairmont, WV
Posts: 1,558
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Quote:
Also, it does look like the exhaust may need to route around some bracing on the convertible models. I suppose the exhaust could have been designed first and the bracing just took advantage of the space, but that seems unlikely. GM simply using a single part that would work for both the coupe and convertible models seems very reasonable. Maybe after some of the other burning questions get answered, we can get an official answer from Al.
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02-02-2018, 11:45 AM | #17 | |
Drives: 2017 Camaro 1SS M6 Join Date: Apr 2015
Location: Indy
Posts: 2,460
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Quote:
Mishimoto already ran a back to back test showing transparency between the crimp and full tube in that section of the exhaust: https://www.mishimoto.com/engineerin...he-crimp-myth/ The crimp definitely reduces cross sectional area (significantly), but is so far downstream from the combustion chamber that the exhaust gas has cooled substantially and does not cause much impact on the torque curve of an otherwise stock car. As HP levels (and exhaust flow) increase, I'd expect that could be a bigger factor. For similar reasons, the stock SS exhaust produces about the same torque/power curve as the optional NPP exhaust.
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2017 Camaro 1SS, M6, Hurst shifter, Hyper Blue, NPP, Gray Split Spoke Wheels
Best 1/4 Mile: 12.24 @ 115.9 mph |
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02-02-2018, 12:00 PM | #18 |
Drives: 2013 Triple Black ZL1 Vert M6 ECF Join Date: Mar 2011
Location: Trenton, Michigan
Posts: 7,047
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It'd be great if we could simply find someone with a ZL1 convertible that'd be willing to take a few photo's of their chassis where the exhaust crimps are to confirm positively that the crimped portion does indeed coincide with the vert chassis bracing.
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02-02-2018, 03:43 PM | #19 |
Drives: 2017 2lt rs Join Date: May 2017
Location: Ontario canada
Posts: 332
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2lt has same crimps,I think it's a ground clearance issue as well as suspension clearances
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02-02-2018, 06:47 PM | #20 |
Drives: 2017 Camaro 2SS Convertible Join Date: Sep 2017
Location: Atlanta, GA.
Posts: 210
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I have a 2ss vert and have seen these crimps. Didn’t pay to much attention. I’ll crawl under ther in the morning and get some pics. I have the braces unber there also but can’t remember exactly how it all lines up. Will update in the am.
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02-02-2018, 07:14 PM | #21 | |
SABIO
Drives: 2016 CAMARO 1SS Join Date: Jul 2015
Location: Bradford, ON
Posts: 5,012
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...ya. I can see how their test is objective and not bias.
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02-02-2018, 08:48 PM | #22 |
Thank you Al Oppenheiser!
Drives: Red Hot A10 ZL1 Convertible Join Date: Jun 2017
Location: Sarasota, FL
Posts: 4,975
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So is the 3% change in CF the reason the blue line is 3% higher?
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02-02-2018, 08:58 PM | #23 |
Drives: '17 ZL1 Join Date: Jul 2016
Location: Fairmont, WV
Posts: 1,558
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That's not really how it's supposed to work, but I had a similar thought when I first saw the chart.
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02-02-2018, 09:28 PM | #24 | |
Thank you Al Oppenheiser!
Drives: Red Hot A10 ZL1 Convertible Join Date: Jun 2017
Location: Sarasota, FL
Posts: 4,975
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Quote:
Then I’d ask why there was low end torque improvement when a flow restriction should really only benefit the top end when the engine is at max gas output. The whole thing smells a bit off to me. |
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02-02-2018, 09:44 PM | #25 | |
Drives: 2017 Camaro 1SS M6 Join Date: Apr 2015
Location: Indy
Posts: 2,460
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Quote:
That data makes more sense to me.
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2017 Camaro 1SS, M6, Hurst shifter, Hyper Blue, NPP, Gray Split Spoke Wheels
Best 1/4 Mile: 12.24 @ 115.9 mph |
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02-02-2018, 09:47 PM | #26 | ||
I used to be Dragoneye...
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The cross-sectional area of the pipe is virtually unaffected. This was a clever, albeit unconventional solution to an annoying problem. Don't let the look of it get under your skin and waste money that could be spent on a more effective mod. Mishimoto's test is good...this video helps shed some light, too... |
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02-02-2018, 09:49 PM | #27 | |
Drives: Grandad's C2 L89 Join Date: May 2017
Location: 20*51.50N 156*29.60W
Posts: 1,711
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Quote:
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2018 ZL1 1LE sw/PDR
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02-03-2018, 11:31 AM | #28 |
HYPER SS
Drives: 2016 Supercharged 2SS Join Date: Feb 2014
Location: Troy OH
Posts: 1,252
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With this dead horse, hopefully this will put this to bed.
We (the company I work for) build the exhaust for our cars, we (along with GM) develop this exhaust to perform a specific way. With out revealing details, I can assure you the crimped section DOES NOT lose or gain HP in any way shape or form. Doe it have a hindrance on sound? maybe to a slight degree that you would have to have the best ears possible to even identify it. Prior to the release of our cars, it has been tested for probably 18 months before its reveal. I hope this clears it up.
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Ordered: 1/15/2016
2000 status 02/01/16 3000 status 02/29/16 3400 status 03/07/16 TPW of 03/14/16 4200 status 03/17/16 in transit! Delivered 03/23/16 2SS Hyper Blue | 6M | NPP | Mag ride | ceramic white Int. | Black out bow ties | P3 Gauge| Front splitter. | 6 pot upgraded brembo brakes. | Magnuson Supercharger/95MM pulley | Rotofab Intake | ZL1 side skirts | HRE FF04 wheels - Michelin PSS4 | ZL1 add ons rock guards and lift points. | AWE touring - resinated catback with link pipes. |
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