Wired exhuast butterfly valves open - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

13BRM2SSRS · 04-29-2015, 10:17 PM

Made it a bit louder at startup and idle for sure. Only drove a few miles so not sure how much difference it makes when cruising around but at least this was a free mod!!!

revived · 04-29-2015, 10:26 PM

Can't you just pull a fuse instead?

13BRM2SSRS · 04-30-2015, 07:53 AM

No L99 verts have mechanical spring loaded valves in the exhaust to muffle the exhuast when AFM switches to 4 cylinder mode.

camguynj · 04-30-2015, 09:37 AM

Quote:

Originally Posted by 13BRM2SSRS

No L99 verts have mechanical spring loaded valves in the exhaust to muffle the exhuast when AFM switches to 4 cylinder mode.

Do you have the NPP exhaust ?

Enduring · 04-30-2015, 09:52 AM

Quote:

Originally Posted by camguynj

Do you have the NPP exhaust ?

NPP is only on option on an LS3.

camguynj · 04-30-2015, 11:00 AM

Quote:

Originally Posted by Enduring

NPP is only on option on an LS3.

That's what I thought. So L99s have exhaust flaps too for AFM ...hmmm

ucHuskies · 04-30-2015, 11:04 AM

Quote:

Originally Posted by 13BRM2SSRS

Made it a bit louder at startup and idle for sure. Only drove a few miles so not sure how much difference it makes when cruising around but at least this was a free mod!!!

Do all L99 have this or just verts? I've seen mixed answers to that. Will check mine when I get home.

Can you post a pic of the work you did?

Enduring · 04-30-2015, 11:44 AM

Only the verts have the extra AFM valves. The first picture is a stock L99 vert exhaust on the right and stock LS3 exhaust on the left. The second picture is a stock L99 coupe exhaust. You can see the spring loaded valve isn't there on the second picture.

Also, no wonder people say the L99 sounds like crap, that huge resonator in the middle kills the sound and the L99 muffler has a j-pipe inside of it (pictures here: http://www.camaro5.com/forums/showthread.php?t=275828)

ucHuskies · 04-30-2015, 09:01 PM

Damn. You're right. Confirmed on my car. Was hoping this would be the fastest way to liven up my sound a bit!!

04-29-2015, 10:17 PM	#1
13BRM2SSRS Drives: 13 Camaro 2SS Vert L99 Join Date: Jul 2014 Location: Florida Posts: 632 View My Garage	Wired exhuast butterfly valves open Made it a bit louder at startup and idle for sure. Only drove a few miles so not sure how much difference it makes when cruising around but at least this was a free mod!!! __________________ Black GFX / Dynatech Supermaxx LT Headers / FR Black Chrome ZL1 Replicas 275/315 / RDP Tune / CAI / VMAX TB / MBRP SS Catback / Gtechniq CSL & EXOV3 / VTC / RX Catch Can / Valentine 1 / Halo DRL / LED Fogs

04-29-2015, 10:26 PM	#2
revived Vrrrm. Drives: 2011 2SS/RS LS3 Join Date: Jun 2013 Location: MA Posts: 1,495	Can't you just pull a fuse instead? __________________

04-30-2015, 07:53 AM	#3
13BRM2SSRS Drives: 13 Camaro 2SS Vert L99 Join Date: Jul 2014 Location: Florida Posts: 632 View My Garage	No L99 verts have mechanical spring loaded valves in the exhaust to muffle the exhuast when AFM switches to 4 cylinder mode. __________________ Black GFX / Dynatech Supermaxx LT Headers / FR Black Chrome ZL1 Replicas 275/315 / RDP Tune / CAI / VMAX TB / MBRP SS Catback / Gtechniq CSL & EXOV3 / VTC / RX Catch Can / Valentine 1 / Halo DRL / LED Fogs

04-30-2015, 11:44 AM	#8
Enduring Drives: 2013 2SS/RS M6 Join Date: May 2014 Location: Canada Posts: 203 View My Garage	Only the verts have the extra AFM valves. The first picture is a stock L99 vert exhaust on the right and stock LS3 exhaust on the left. The second picture is a stock L99 coupe exhaust. You can see the spring loaded valve isn't there on the second picture. Also, no wonder people say the L99 sounds like crap, that huge resonator in the middle kills the sound and the L99 muffler has a j-pipe inside of it (pictures here: http://www.camaro5.com/forums/showthread.php?t=275828)

04-30-2015, 09:01 PM	#9
ucHuskies Drives: 2014 SS/RS Blue Ray Join Date: Mar 2015 Location: Long Island, NY Posts: 67	Damn. You're right. Confirmed on my car. Was hoping this would be the fastest way to liven up my sound a bit!!