GS Mufflers Have Valves (Photo)

Jack GS

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Maybe some of you were already aware of this, but I was looking around and found out the mufflers on the GS have valves. I could press on it and get it to rotate. There aren't any wires going to it that I could see so I believe it functions solely on pressure. At idle, they're still closed. This must be part of our "sport tuned exhaust".

14444
 
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1500cc

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Neat! Based on the offset pivot point, they definitely need pressure to open.

Given the dirty, sooty environment that they live in, I'd recommend the frequent use of full throttle to keep them loose so that they don't seize ;)
 

TricoatGS

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Maybe some of you were already aware of this, but I was looking around and found out the mufflers on the GS have valves. I could press on it and get it to rotate. There aren't any wires going to it that I could see so I believe it functions solely on pressure. At idle, they're still closed. This must be part of our "sport tuned exhaust".

View attachment 14444
I'm not sure if it's there for noise, this winter I noticed on my GS, we get extreme cold here, like -50 C at times. When It got really cold after remote starting the car i noticed the car would actually close one tailpipe so I could only see exhaust coming out of one pipe, probably to warm the engine up, keep heat inside the engine instead of wasting it by letting it all go out.
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L J

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Probably stronger spring on one, assuming they are not duals all the way, probably use one bigger pipe for part of system.
 

RiojaTourX

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I'd bet it has to do with cylinder deactivation if the GS has that.
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L J

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Maybe your right... keeps it from sounding so bad when in cylinder deactivation mode.
 

BahamaTodd

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Someone needs to take a video revving, or manually actuating the valves at idle to see if there is a sound level difference.

Instead of an all new exhaust, maybe a valve delete will be just enough to give more sound.
 

Jack GS

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2019 Buick Regal GS
Since there is some uncertainty on the subject, the GS does not have dual exhaust. GM Parts House:
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I found some more info on the use of valves in mufflers. If the GS muffler is designed similarly to the Dynomax muffler shown below, its sole purpose is to quiet things down at idle and low RPM. They may also reduce drone.

EDIT: I'd also guess the valves affect back pressure and fuel economy to an extent. How much? Your guess is as good as mine.
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I did also notice that the GS muffler has what looks to be a wire wool cushioning the valve. One user in the forum post below commented that the springs and wool can wear out, leaving the valves to rattle around. Reviewers of the Dynomax muffler on the Summit Racing website have similar complaints.

MiataTurbo.net: Loaded Spring Flapper Valve

Hopefully ours last a while. I'll probably leave mine alone unless they start to rattle. Then out they come.
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TricoatGS

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Since there is some uncertainty on the subject, the GS does not have dual exhaust. GM Parts House:
View attachment 14458

I found some more info on the use of valves in mufflers. If the GS muffler is designed similarly to the Dynomax muffler shown below, its sole purpose is to quiet things down at idle and low RPM. They may also reduce drone.

EDIT: I'd also guess the valves affect back pressure and fuel economy to an extent. How much? Your guess is as good as mine.
View attachment 14456

I did also notice that the GS muffler has what looks to be a wire wool cushioning the valve. One users in the forum post below commented that the springs and wool can wear out, leaving the valves to rattle around. Reviewers of the Dynomax muffler on the Summit Racing website have similar complaints.

MiataTurbo.net: Loaded Spring Flapper Valve

Hopefully ours last a while. I'll probably leave mine alone unless they start to rattle. Then out they come.
Thank you for the clarification on the duel exhaust. I wonder if the commodore VXR has that much of a different exhaust as that one sounds amazing!
 

Jack GS

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2019 Buick Regal GS
They do sound amazing! I'm not sure if they're the same or not. For those that haven't been enlightened by the beautiful noises emanating from the VXR...
 

TricoatGS

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They do sound amazing! I'm not sure if they're the same or not. For those that haven't been enlightened by the beautiful noises emanating from the VXR...
Wonder how hard it would be sourcing one of those to systems to north America, see I'd be so happy with that stock, perfect amount of not too loud but not too quiet. Makes me jealous of the aussies lol
 

L J

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Since there is some uncertainty on the subject, the GS does not have dual exhaust. GM Parts House:
View attachment 14458

I found some more info on the use of valves in mufflers. If the GS muffler is designed similarly to the Dynomax muffler shown below, its sole purpose is to quiet things down at idle and low RPM. They may also reduce drone.

EDIT: I'd also guess the valves affect back pressure and fuel economy to an extent. How much? Your guess is as good as mine.
View attachment 14456

I did also notice that the GS muffler has what looks to be a wire wool cushioning the valve. One user in the forum post below commented that the springs and wool can wear out, leaving the valves to rattle around. Reviewers of the Dynomax muffler on the Summit Racing website have similar complaints.

MiataTurbo.net: Loaded Spring Flapper Valve

Hopefully ours last a while. I'll probably leave mine alone unless they start to rattle. Then out they come.
That looks alot like what I recall the Tourx pipes look like.
Except for the fancy tips and flaps.
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L J

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I was wondering if the TourX utilized them. Thanks for the input! It would almost make more sense for the 2.0T to have the valves.
Probably would not help 2.0T since it runs on all cylinders all the time.
 

L J

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But quessing only thing different between GS and TourX exhaust is mufflers with tips and baffles.and of course extra manifold and headpipe.
 

Jack GS

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2019 Buick Regal GS
Probably would not help 2.0T since it runs on all cylinders all the time.
Yeah true, it's probably gonna shine more where AFM or DFM is used. I'd guess the spring valves would be useful for decreasing idle and low RPM noise levels for all engines though. Kinda like the how a lot of the muscle and sport cars have the remote controlled valves so they can meet noise emissions, yet also sound like a performance vehicle when the valves are opened.
 
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