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Exhaust Adaptive Valve

MotoMedic

By MotoMedic
in Engines & Drivetrain

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MotoMedic Senior Enthusiast

MotoMedic

Posted
Posted

Anyone else notice the "adaptive valve" just after the muffler? Looks like it's a simple spring-operated flapper valve. Explains why, when I rev my engine, the intake is louder than the exhaust! ha

Got my Magnaflow 5x8x18 today... add it to this week's "To Install" list.

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CorvetteOJ
CorvetteOJ

Hey Medic, when I read your post, I immeidately remembered when I was a kid, (teenager) guys would stick raw potatoes on the end of someone's exhaust pipe, and in most cases, would get the same effect

iCryWheniGoPoop
iCryWheniGoPoop

What Dave said... whats it going to hurt anyway, just put a $2 hose clamp on it for now and see if you like it. If you don't... crawl back underneath it and take 30 seconds to pull it back off. Its ha

45acp
45acp

I like the hose clamp idea. Cheap and easy to try and if you don't like it take it off.   DJ

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RyanbabZ71 Senior Enthusiast

RyanbabZ71

Posted
Posted

my camaro has that. Need to figure out how to disable one day

BringTheRain403 Senior Enthusiast

BringTheRain403

Posted
Posted
Anyone else notice the "adaptive valve" just after the muffler? Looks like it's a simple spring-operated flapper valve. Explains why, when I rev my engine, the intake is louder than the exhaust! ha

Got my Magnaflow 5x8x18 today... add it to this week's "To Install" list.

 

Before and after video please!

 

Sent from my SCH-I535 using Tapatalk 2

 

 

TimmyG Senior Enthusiast

TimmyG

Posted
Posted

I have seen that on motorcycles but not a car yet

 

Sent from my SCH-I535 using Tapatalk 2

06Voy Enthusiast

06Voy

Posted
Posted

I assume it is the same as what the corvettes have had for several years as an option with the butterfly valve that opens under hard acceleration to make the exhaust louder. There may be a fuse somewhere you can pull that will leave it open.

MotoMedic Senior Enthusiast

MotoMedic

Posted
  • Author
Posted (edited)

It's a dumb-valve, as in spring tension is the only thing that controls opening/closing. Looking at it up close, I'm surprised how inefficient the shape is... maybe it helps the truck perform better when in V4 mode..? Dunno. I'm no exhaust expert, but it sure looks like it would really disrupt any smooth/laminar flow the exhaust might have had.

 

*EDIT: It normally swings both ways freely, but I had to open it in reverse for the pic b/c of the metal slag left over when pipe was cut so close to valve.

post-34923-0-88952400-1374607399_thumb.jpg

post-34923-0-88952400-1374607399_thumb.jpg

post-34923-0-88952400-1374607399_thumb.jpg

post-34923-0-88952400-1374607399_thumb.jpg

Edited by MotoMedic
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MotoMedic Senior Enthusiast

MotoMedic

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Oh yeah, I installed my 5x8x18 Magnaflow muffler today. I decided to leave in the resonator (it's near the spare tire on 2014's) for now so I could judge volume/drone with new muffler. Before there was virtually no sound from the exhaust. Under hard acceleration you could only hear the intake. Now it sounds like a normal truck. A little bit at idle and a good clean sound when accelerating but nothing loud or "look at me" annoying. For those that want to be heard, I definitely suggest removing the resonator and going with a smaller muffler (that's if you're buying the straight flow-through style; chambered mufflers like Flowmaster might sound completely different).

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  • 2 weeks later...
b1gted Enthusiast

b1gted

Posted
Posted

How does it sound in V4 mode and switching in and out of V4/V8 mode?

MotoMedic Senior Enthusiast

MotoMedic

Posted
  • Author
Posted

From inside the cab, there's no sound when in V4 mode. V8 has a nice low rumble.

Basically the same as the GMT-900's when switching.

cobrajet84 Senior Enthusiast

cobrajet84

Posted
Posted

This has nothing to do with your exhaust motomedic, but on your truck did you get both the sliding and defrost rear glass, was building online and trying to figure out which configurations had it.

BringTheRain403 Senior Enthusiast

BringTheRain403

Posted
Posted
This has nothing to do with your exhaust motomedic, but on your truck did you get both the sliding and defrost rear glass, was building online and trying to figure out which configurations had it.

 

The preferred package has it...

 

Sent from my SCH-I535 using Tapatalk 2

 

 

cobrajet84 Senior Enthusiast

cobrajet84

Posted
Posted

The preferred package has it... Sent from my SCH-I535 using Tapatalk 2

cool thanks, sorry to hijack the exhaust thread.

  • 1 month later...
GPlancarte Enthusiast

GPlancarte

Posted
Posted

Oh yeah, I installed my 5x8x18 Magnaflow muffler today. I decided to leave in the resonator (it's near the spare tire on 2014's) for now so I could judge volume/drone with new muffler. Before there was virtually no sound from the exhaust. Under hard acceleration you could only hear the intake. Now it sounds like a normal truck. A little bit at idle and a good clean sound when accelerating but nothing loud or "look at me" annoying. For those that want to be heard, I definitely suggest removing the resonator and going with a smaller muffler (that's if you're buying the straight flow-through style; chambered mufflers like Flowmaster might sound completely different).

would replacing the stock muffler void the warranty because of that valve?

BringTheRain403 Senior Enthusiast

BringTheRain403

Posted
Posted

In order for something to void the warranty they would need to prove that the issue you were having was caused by the modification...

 

 

 

Sent from my Galaxy Nexus using Tapatalk 2

 

 

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