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2019-2020 6.2 muffler swap info

DaveHC
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Dman10 Enthusiast

Dman10

Posted
Posted

I went with the MF 11229. 3" in and out as the flapper valve drops down to near 3" into and out the stock muffler and had removed the rear flapper. Wow start up, idle and throttle sound great. Cruising not so much, you can hear the DFM, and it sounds busy switching all the time, and there is drone in DFM mode while under load till more cylinders activate. Ill be getting the rear flapper put back in, I am sure it'll kill the startup rumble but the on throttle sound will be great and the dfm chop and drone should be gone. 

mrtizzom Enthusiast

mrtizzom

Posted
Posted

Did you leave the downstream or upstream flapper in place?? How does it sound??

 

RyanbabZ71 Senior Enthusiast

RyanbabZ71

Posted
Posted

This “kit” leaves the upstream flapper. It sounds good takes time to get used to. When you hit the gas it’s pretty throaty [emoji16]cruising its quiet

 

 

Ryan B.

 

BluegrassMotorsport Enthusiast

BluegrassMotorsport

Posted
Posted

I ended up having mine done a couple of weeks ago. I had them delete the muffler and leave both flappers. And I left all the resonator mesh uncovered. Man, what a difference! There's no drone on the highway until around 80-85mph and only slight DFM noises every now and then. It only cost me $75 and I can't believe I almost considered dropping $1400 on the whole system after hearing mine now.

 

Here's some quick examples:

 

 

  • Like 2
Dman10 Enthusiast

Dman10

Posted
Posted (edited)
On 10/5/2020 at 8:02 PM, Dman10 said:

I went with the MF 11229. 3" in and out as the flapper valve drops down to near 3" into and out the stock muffler and had removed the rear flapper. Wow start up, idle and throttle sound great. Cruising not so much, you can hear the DFM, and it sounds busy switching all the time, and there is drone in DFM mode while under load till more cylinders activate. Ill be getting the rear flapper put back in, I am sure it'll kill the startup rumble but the on throttle sound will be great and the dfm chop and drone should be gone. 

Update. The installer put the pipe inside the adaptive valve and the counter weight got stuck open. So now that its addressed it sounds awesome cruising. You can hear the DFM but its not intrusive. Any one with the delete or muffler swap that kept front flappers in place get rid of the resonators. Have a sound clip

Edited by Dman10
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SILVER SLED Senior Enthusiast

SILVER SLED

Posted
Posted
2 hours ago, Dman10 said:

Update. The installer put the pipe inside the adaptive valve and the counter weight got stuck open. So now that its addressed it sounds awesome cruising. You can hear the DFM but its not intrusive. Any one with the delete or muffler swap that kept front flappers in place get rid of the resonators. Have a sound clip

So they stuck a smaller pipe inside the already small pipe that contains the flapper?

 

 

 

RyanbabZ71 Senior Enthusiast

RyanbabZ71

Posted
Posted
So they stuck a smaller pipe inside the already small pipe that contains the flapper?
 
 
 


[emoji848] how did that happen? I don’t think the delete pipe could fit inside then stock pipe unless they modified it to jam it in [emoji2373]


Ryan B.
Dman10 Enthusiast

Dman10

Posted
Posted

He did. The adaptive valve is like 3-1/8", he stuck a 3" pipe in there feeding the 11229 mf. Its now sorted and the pipe is over the adaptive valve pipe. 

Dman10 Enthusiast

Dman10

Posted
Posted

Stock is 3.0" muffler in out.

However stock pipe is 3.5" that drops down to 3.16" for the adaptive valve to 3" into muffler. If you delete everything 36" of 3.5" should span the gap, if you"re keeping the adaptive valve you'll need to have a muffler shop flare an end or buy a muffler delete pipe like magnaflow sells.

  • Like 1
SILVER SLED Senior Enthusiast

SILVER SLED

Posted
Posted

I have a 4" in 4" out offset piece of exhaust piping about 40" long I may just have a muffler shop slide over the 3 1/2 and then make a piece at the back of the the piping to adapt to the 3 1/2 stock piping.  

  • 3 weeks later...
Scooter Scott Enthusiast

Scooter Scott

Posted
Posted
On 10/7/2020 at 11:04 AM, BluegrassMotorsport said:

I ended up having mine done a couple of weeks ago. I had them delete the muffler and leave both flappers. And I left all the resonator mesh uncovered. Man, what a difference! There's no drone on the highway until around 80-85mph and only slight DFM noises every now and then. It only cost me $75 and I can't believe I almost considered dropping $1400 on the whole system after hearing mine now.

 

Here's some quick examples:

 

 

Would love to hear additional sound bits of drive-bys and under load.

Rob Mugs Enthusiast

Rob Mugs

Posted
Posted
On 11/9/2020 at 8:06 AM, Scooter Scott said:

Would love to hear additional sound bits of drive-bys and under load.

+1

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