2013 2SS / RS dual mode performance exhaust question - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

gow-92 · 10-19-2012, 11:04 AM

So I just bought a brand new black 2SS / RS manual with a dual mode performance exhaust. The car had a lot of plastic and only 4 miles on it when I took it for a test drive.

I noticed that the flaps inside both sides of the exhaust appear to always be open regardless of engine rpm. After researching about how the corvette version of this exhaust works, I don't think this is working correctly. The chevy dealer seems to think this is correct. Does anyone else have a 2013 with this exhaust know how is this supposed to work? I included a picture that shows what I'm talking about.

slick rick · 10-19-2012, 11:32 AM

When you're on the highway at cruising speed/low RPM, you don't hear the exhaust sound change?

RollaMo · 10-19-2012, 11:40 AM

A GM engineer I talked to while on Power Tour explained them to me this way.
I was in one of the hotel parking lots where they were staying, when he came out and started the ZL1 they were driving.

At idle, they are open so you have a louder more agressive sound.
As you begin moving (during a slow drive by for instance), they will close up to make the exhaust system quieter.

The federal sound level test they have to pass, is conducted during a slow drive by.
So, GM designed the system to be quieter during this test process.

At idle and wide open throttle, they should be open.
Low rpm cruising, the exhaust should be much quieter.

gow-92 · 10-19-2012, 11:42 AM

No, its always rumbly. I have revved the engine a little and confirmed the position of those flaps don't change regardless of engine rpm.

ROD_SS · 10-19-2012, 11:50 AM

Maybe the fuse has been pulled already?

Something to check out

Jim968 · 10-19-2012, 12:45 PM

Quote:

Originally Posted by RollaMo

A GM engineer I talked to while on Power Tour explained them to me this way.
I was in one of the hotel parking lots where they were staying, when he came out and started the ZL1 they were driving.

At idle, they are open so you have a louder more agressive sound.
As you begin moving (during a slow drive by for instance), they will close up to make the exhaust system quieter.

The federal sound level test they have to pass, is conducted during a slow drive by.
So, GM designed the system to be quieter during this test process.

At idle and wide open throttle, they should be open.
Low rpm cruising, the exhaust should be much quieter.

This is exactly how it works on my 2013 SS.

Ehmsea · 10-19-2012, 01:36 PM

start the car and have someone take it up to about 1500 RPM and hold it. The butterfly valve on the outboard exhaust should close just after 1000 RPMs.
If it does not close by 1500 RPM, something is wrong. I'd say the fuse, but I believe when the fuse blows that it will be closed...

If your tester was reving it up and down, the computer may have left the valves open as it interpreted your throttle inputs as aggressive...

Edwin320 · 10-19-2012, 01:44 PM

I think they are also dependent on engine load. Revving in a parking lot doesn't put a load on the motor. Attach a GoPro pointing at the valve and go for a ride. You'll see the butterfly move.

gow-92 · 10-19-2012, 01:45 PM

Good point. I don't think we tried gently bringing it into the 1000 - 3000 range and letting it sit there for a bit. I'll test later today.

thepirate · 10-19-2012, 02:52 PM

does it maybe have to do with the car actually moving and going into different gears at different RMPs??

I have the same set up and have been looking into disabling it for a "always aggressive sound" i'll probably try the rear fuse pull at some point.

HDRDTD · 10-19-2012, 03:43 PM

The valves are open at idle when you first fire it up on purpose.

They'll close once you are cruising along at a steady speed and the vacumn is high.

Step on the throttle, vacumn goes down and the valves open up while you're accelerating.

At least that's the way it works on my ZL1.

gow-92 · 10-21-2012, 10:53 AM

I played around with this a little last night with the car in my driveway. The valves appear to close starting at around 1500 RPM.

2008yellow · 10-21-2012, 03:23 PM

I have a 13 with this exhaust it works the way they described. In my ZO6 Vette the pipes stayed closed until about 3,000 RPM sand then opened. unless you pulled fuse or put on mild to wild. It sounds like your Camaro is working the way it should , like mine. One thing my Camarrow is louder than the ZO6.

10-19-2012, 11:04 AM	#1
gow-92 Drives: 2013 2SS / RS Join Date: Nov 2010 Location: StL Posts: 24 View My Garage	2013 2SS / RS dual mode performance exhaust question So I just bought a brand new black 2SS / RS manual with a dual mode performance exhaust. The car had a lot of plastic and only 4 miles on it when I took it for a test drive. I noticed that the flaps inside both sides of the exhaust appear to always be open regardless of engine rpm. After researching about how the corvette version of this exhaust works, I don't think this is working correctly. The chevy dealer seems to think this is correct. Does anyone else have a 2013 with this exhaust know how is this supposed to work? I included a picture that shows what I'm talking about. Attached Images

10-19-2012, 11:32 AM	#2
slick rick SoCal Mayhem Drives: 2010 Camaro 1SS/RS Join Date: Aug 2008 Location: Foothill Ranch, CA Posts: 5,488 View My Garage	When you're on the highway at cruising speed/low RPM, you don't hear the exhaust sound change? __________________

10-19-2012, 11:40 AM	#3
RollaMo Drives: 2017 2SS Join Date: Mar 2012 Location: Rolla, MO Posts: 1,106	A GM engineer I talked to while on Power Tour explained them to me this way. I was in one of the hotel parking lots where they were staying, when he came out and started the ZL1 they were driving. At idle, they are open so you have a louder more agressive sound. As you begin moving (during a slow drive by for instance), they will close up to make the exhaust system quieter. The federal sound level test they have to pass, is conducted during a slow drive by. So, GM designed the system to be quieter during this test process. At idle and wide open throttle, they should be open. Low rpm cruising, the exhaust should be much quieter. __________________ 1996 Corvette - LT4 2017 Camaro 2SS 2019 GMC Sierra 2500 HD 2015 Harley Davidson Ultra Limited

10-19-2012, 11:50 AM	#5
ROD_SS Drives: 2013 1SS Camaro and a truck Join Date: Apr 2011 Location: San Antonio,TX Posts: 1,081	Maybe the fuse has been pulled already? Something to check out __________________ ADM tuned (465 rwhp / 442 torque) Mods- CAI, kooks long tube headers, & ADM stage 2 cam

10-19-2012, 01:36 PM	#7
Ehmsea Drives: 2013 2SS RS Hurst NPP Join Date: May 2012 Location: Perrysburg, OH Posts: 233 View My Garage	start the car and have someone take it up to about 1500 RPM and hold it. The butterfly valve on the outboard exhaust should close just after 1000 RPMs. If it does not close by 1500 RPM, something is wrong. I'd say the fuse, but I believe when the fuse blows that it will be closed... If your tester was reving it up and down, the computer may have left the valves open as it interpreted your throttle inputs as aggressive... __________________ No Worries CAI Intake w/washer relocation and race scoop Ported Throttle Body (Polished) Kooks LT stepped headers 1-3/4 to 1-7/8 High Flow Cats Livernois Motorsports Stage 2c Cam Package https://www.youtube.com/watch?v=AKXyCyBh9BU Hill Start Assist Delete

10-19-2012, 11:42 AM	#4
gow-92 Drives: 2013 2SS / RS Join Date: Nov 2010 Location: StL Posts: 24 View My Garage	No, its always rumbly. I have revved the engine a little and confirmed the position of those flaps don't change regardless of engine rpm.

10-19-2012, 01:44 PM	#8
Edwin320 Drives: 2018 Camaro ZL1 Convertible A10 Join Date: Mar 2012 Location: Miami, Fl Posts: 427 View My Garage	I think they are also dependent on engine load. Revving in a parking lot doesn't put a load on the motor. Attach a GoPro pointing at the valve and go for a ride. You'll see the butterfly move. __________________ Ed 2018 ZL1 A10 'Vert

10-19-2012, 01:45 PM	#9
gow-92 Drives: 2013 2SS / RS Join Date: Nov 2010 Location: StL Posts: 24 View My Garage	Good point. I don't think we tried gently bringing it into the 1000 - 3000 range and letting it sit there for a bit. I'll test later today.

10-19-2012, 02:52 PM	#10
thepirate Drives: 2013 2SS Join Date: Aug 2012 Location: Salt Lake City, UT Posts: 372	does it maybe have to do with the car actually moving and going into different gears at different RMPs?? I have the same set up and have been looking into disabling it for a "always aggressive sound" i'll probably try the rear fuse pull at some point. __________________

10-19-2012, 03:43 PM	#11
HDRDTD Drives: 2013 Triple Black ZL1 Vert M6 ECF Join Date: Mar 2011 Location: Trenton, Michigan Posts: 7,047	The valves are open at idle when you first fire it up on purpose. They'll close once you are cruising along at a steady speed and the vacumn is high. Step on the throttle, vacumn goes down and the valves open up while you're accelerating. At least that's the way it works on my ZL1.

10-21-2012, 10:53 AM	#12
gow-92 Drives: 2013 2SS / RS Join Date: Nov 2010 Location: StL Posts: 24 View My Garage	I played around with this a little last night with the car in my driveway. The valves appear to close starting at around 1500 RPM.

10-21-2012, 03:23 PM	#13
2008yellow Drives: 2013 blue Join Date: Jul 2012 Location: pa. Posts: 94	engineer icorrect surprise I have a 13 with this exhaust it works the way they described. In my ZO6 Vette the pipes stayed closed until about 3,000 RPM sand then opened. unless you pulled fuse or put on mild to wild. It sounds like your Camaro is working the way it should , like mine. One thing my Camarrow is louder than the ZO6.