Performance exhaust
Thread Starter
Navigator
Joined: Nov 2013
Posts: 9
Likes: 0
From: BARTLETT (MEMPHIS) TN
Performance exhaust
I have a 2014 3lt (NOT a Z51) and when set to Sport OR Track, the exhaust indeed does what it is supposed to do BUT after a few moments, the open sound suddenly shuts and goes to the quiet exhaust sound. The only way to get the louder sound to return is to aggressively and briefly accelerate and the through sound returns for a few moments.
I have been told that the sound should never change to quiet as long as the car is in the Sport or Track mode.
Can someone help and let me know which are the facts. Remember NON Z51 but the car DOES have the performance exhaust option.
Thanks
Ray
I think i must have asked the wrong question
does anyone out there have a 2014 C7 Stingray that has the performance exhaust and if so,,,,,,,does the great sound of the Sport and/or Track mode stay on as long as your car is in either of these two mode OR
does it shut off after a few seconds . in other words,, does anyone have the same issue as i stated above. i am not looking for solutions, only identifying anyone with the same concerns
Thanks
Ray
I have been told that the sound should never change to quiet as long as the car is in the Sport or Track mode.
Can someone help and let me know which are the facts. Remember NON Z51 but the car DOES have the performance exhaust option.
Thanks
Ray
I think i must have asked the wrong question
does anyone out there have a 2014 C7 Stingray that has the performance exhaust and if so,,,,,,,does the great sound of the Sport and/or Track mode stay on as long as your car is in either of these two mode OR
does it shut off after a few seconds . in other words,, does anyone have the same issue as i stated above. i am not looking for solutions, only identifying anyone with the same concerns
Thanks
Ray
Last edited by RAY P.; Mar 15, 2014 at 08:28 PM. Reason: UPDATE THE QUESTION
Drifting
Joined: Mar 2002
Posts: 1,687
Likes: 9
From: Kemah Tx
I seem to remember reading that this in fact does keep the valves aft of the mufflers open but does not control the valves ahead of the mufflers???...meaning that you still aren't getting wide open sound unless you stomp on it. Is this true?? I do not possess my car yet so I am speculating on what I have read....
Moderator
Joined: Feb 2006
Posts: 39,054
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From: DFW Area TX
I seem to remember reading that this in fact does keep the valves aft of the mufflers open but does not control the valves ahead of the mufflers???...meaning that you still aren't getting wide open sound unless you stomp on it. Is this true?? I do not possess my car yet so I am speculating on what I have read....
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Joined: Feb 2006
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From: DFW Area TX
Here's some photos (thanks to talon90) of the NPP (and ECO valves). The ECO valves are before the mufflers and the NPP are the valves after the muffler - right before the exhaust tip):
The NPP valve opens up a less restrictive path through the muffler that results in less back-pressure, more HP and torque and a louder exhaust sound.
The non-NPP exhaust has the ECO valve and only a single outlet pipe from the muffler that the splits into the 4 exhaust tips. No NPP valve.
The NPP valve opens up a less restrictive path through the muffler that results in less back-pressure, more HP and torque and a louder exhaust sound.
The non-NPP exhaust has the ECO valve and only a single outlet pipe from the muffler that the splits into the 4 exhaust tips. No NPP valve.
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Joined: Feb 2006
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From: DFW Area TX
Melting Slicks
Joined: Sep 2009
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From: Mooresville North Carolina
St. Jude Donor '10-'11-'12-'13-'14-'15-'16-'17-'18
and learning!
Drifting
Joined: Jun 2013
Posts: 1,764
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From: Cumming GA
On order: Torch Red Z51
It does get quieter after a short distance. This is what mine sounds like in the garage when she wakes up in the morning. My neighbors get to hear it too 
. Fortunately the closest one on the garage side is a gear head 
.
. Fortunately the closest one on the garage side is a gear head .I have a 2014 3lt (NOT a Z51) and when set to Sport OR Track, the exhaust indeed does what it is supposed to do BUT after a few moments, the open sound suddenly shuts and goes to the quiet exhaust sound. The only way to get the louder sound to return is to aggressively and briefly accelerate and the through sound returns for a few moments.
I have been told that the sound should never change to quiet as long as the car is in the Sport or Track mode.
Can someone help and let me know which are the facts. Remember NON Z51 but the car DOES have the performance exhaust option.
Thanks
Ray
I think i must have asked the wrong question
does anyone out there have a 2014 C7 Stingray that has the performance exhaust and if so,,,,,,,does the great sound of the Sport and/or Track mode stay on as long as your car is in either of these two mode OR
does it shut off after a few seconds . in other words,, does anyone have the same issue as i stated above. i am not looking for solutions, only identifying anyone with the same concerns
Thanks
Ray
I have been told that the sound should never change to quiet as long as the car is in the Sport or Track mode.
Can someone help and let me know which are the facts. Remember NON Z51 but the car DOES have the performance exhaust option.
Thanks
Ray
I think i must have asked the wrong question
does anyone out there have a 2014 C7 Stingray that has the performance exhaust and if so,,,,,,,does the great sound of the Sport and/or Track mode stay on as long as your car is in either of these two mode OR
does it shut off after a few seconds . in other words,, does anyone have the same issue as i stated above. i am not looking for solutions, only identifying anyone with the same concerns
Thanks
Ray
Race Director
Joined: Jun 2000
Posts: 13,733
Likes: 66
From: Hurst, TX USA
When I switch to Sport mode while driving the exhaust gets instantly louder and stays that way. It gets even louder if I accelerate briskly then quiets down when cruising, as you would expect. But i doesn't get as quiet as it would if I switched back to Touring or Eco. I do not have the Driving Mode > Engine Sound Management > set to OFF.
Sounds to me like the OP's car is operating normally.
Sounds to me like the OP's car is operating normally.
Melting Slicks
Joined: Apr 2005
Posts: 2,045
Likes: 4
From: Yorktown VA
NCM Sinkhole Donor
AFM is not an issue in Sport or Track mode, at least with mine. For 7spd man, it only works in Eco mode. In the Auto 6, I believe it works in touring as well, not sure about Sport or Track.
". Normal with automatic
transmission: The engine uses
8-cylinder mode when
accelerating, but changes to
4-cylinder mode when coasting.
. With manual transmission:
Active Fuel Management only
active in Eco Mode.
. Off in Manual mode with
automatic transmission unless in
Eco mode"
I have the exhaust turned off so it stays loud in all modes, however, my M7 doesn't get real loud unless you step on the gas.
". Normal with automatic
transmission: The engine uses
8-cylinder mode when
accelerating, but changes to
4-cylinder mode when coasting.
. With manual transmission:
Active Fuel Management only
active in Eco Mode.
. Off in Manual mode with
automatic transmission unless in
Eco mode"
I have the exhaust turned off so it stays loud in all modes, however, my M7 doesn't get real loud unless you step on the gas.