03-25-2019, 09:17 PM | #141 | ||
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
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Quote:
https://youtu.be/rMmg8eJdqC4
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2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
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03-26-2019, 07:23 AM | #142 | |
Drives: 2017 Camaro SS 1970 chevelle SS Join Date: Oct 2016
Location: Florida
Posts: 231
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Flowmaster American Thunder Dual Mode Axle-back (NPP) for 2016+ Camaro SS & ZL1
Quote:
Yea mine definitely doesn’t sound like that when closed. I wonder if your valves have gotten dirty somehow or collected buildup which may keep them from fully closing? Sent from my iPhone using Tapatalk
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2017 camaro SS A8
FBO With all porting and tuning done by PRAY |
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03-26-2019, 08:57 AM | #143 |
Drives: 2016 SS w/2SS A8 Blue Velvet Join Date: Dec 2009
Location: 39.793153,-86.238223
Posts: 3,678
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Mine either.... as stated above, maybe some build up on them? Wonder if maybe shooting them with some carb cleaner and using an old tooth brush and then spraying again might resolve the issue. I’ve have mine virtually since getting the car new in 2016 and still sounds great and seemed to have gotten deeper along the way.
I’d like to do headers but seems as tho they won’t mate up to the Scavenger X so I’ve been told and ARH and KOOKS wants to sell be a catback, tho MOTOFIRE on IG says it will work. Just need confirmation before I make that move but I can only imagine what it would sound like..... Sent from my iPhone using Tapatalk
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Never grow up, it's a trap!
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03-26-2019, 09:18 AM | #144 |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
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The exhaust is brand new. I even tried oiling the valve shafts. When I shine a light in the pipe, the valve doesn't look concentric with the pipe. I must of received a axle back built on a Monday.
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2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
04-05-2019, 06:00 PM | #145 |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
|
Still no word yet from Flowmaster. CS rep said he is still waiting to hear back from the product group.
__________________
2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
04-05-2019, 06:11 PM | #146 | |
Drives: 2017 Camaro SS 1970 chevelle SS Join Date: Oct 2016
Location: Florida
Posts: 231
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Quote:
While I have not noticed the noise that yours makes, I have noticed that my valves don’t shut 100%. Essentially I can put mine in stealth mode, and still get some flow on the outer pipes. It gets quieter if I cover the outer pipes with my hands. I assumed this was just the nature of these valved exhausts, but it could be related to the problem you are experiencing. Sent from my iPhone using Tapatalk
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2017 camaro SS A8
FBO With all porting and tuning done by PRAY |
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04-05-2019, 06:37 PM | #147 | |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
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Quote:
I'm going to try some stuff in the exhaust valve tuning and see if I can fix it. It almost seems like the valves need to be turned a tad further then the controller is turning them in order to seal. I am going to try using a value higher then 100 in the closed cells and see what happens.
__________________
2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
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04-05-2019, 07:18 PM | #148 |
Drives: 6th gen Join Date: Aug 2013
Location: US
Posts: 3,710
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Anyway to cheat on the valves and get them to turn a bit in that direction and retorque the bolts? Are they the oem actuators that boot in there?
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04-05-2019, 09:08 PM | #149 |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
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Yeah OEM actuators. I'm going to try some things and see what happens.
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2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
04-07-2019, 02:54 PM | #150 |
Drives: 2017 Hyper Blue 1LE Join Date: Dec 2016
Location: Tampa
Posts: 579
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Mine has that hissing sound with the valves closed too. Much better than the stock "rattle" but still annoying.
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04-08-2019, 08:37 AM | #151 |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
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Thanks for reporting. Yes I agree, I will just leave the valves open at idle and cruising, then have them close in 8th gear so it eliminates the drone.
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2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
04-08-2019, 08:39 AM | #152 |
Drives: 6th gen Join Date: Aug 2013
Location: US
Posts: 3,710
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Does it hiss at the low cfm at cruise or just when pushing a bunch of air through them?
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‘22 2SS 1LE M6 Summit White - RF, Flexfuel, LT2 intake, 95mm tb, ATI udp, VT ramair, full 28” dragpack - 11.68@122
‘16 1SS M6 LT2 intake + boltons on DR 11.0@126+ (Sold) |
04-08-2019, 09:24 AM | #153 |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
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its only noticeable at idle with the exhaust valves closed(touring/stealth) when you stand behind the car, or backing into the garage with the windows down. Most probably leave the car in sport and never notice it, but since I have cat deletes, it makes the exhaust significantly louder. I had my valves programmed to stay closed in all modes until 3-4k rpm then open.
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2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
05-06-2019, 09:37 PM | #154 |
Drives: 2016 1SS NFG A8 Join Date: Aug 2017
Location: 46804
Posts: 6,951
|
Just an update...Holley performance group is sending me a brand new axle back exhaust. It's been a slow process but nonetheless they are taking care of me.
__________________
2016 NFG 1SS A8
Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA |
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Tags |
american, axle, dual, flowmaster, npp |
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