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So I’ve been driving it around a bit. Definitely notice it to be a bit deeper in tone. Nothing crazy, but there is a difference for the better. Makes me want to cut my muffler off now


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5 hours ago, Thejet07 said:

So I’ve been driving it around a bit. Definitely notice it to be a bit deeper in tone. Nothing crazy, but there is a difference for the better. Makes me want to cut my muffler off now


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Lol I had that thought, too, after a week with the mod. It whets your appetite for even more throaty noise! 

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Everytime I did an aftermarket I always got sick of it and went back to stock. I think this mod is just right. Think if I did a mod it would be an electric cutout for just a little fun now and again. A few members on here have done that already.

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16 minutes ago, ShamrockShooter said:

Everytime I did an aftermarket I always got sick of it and went back to stock. I think this mod is just right. Think if I did a mod it would be an electric cutout for just a little fun now and again. A few members on here have done that already.

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Yeah, I agree. This is why I like this mod. Subtle, but makes a difference. I know for sure that I would not enjoy a true exhaust tune. The electric catback is the only way I could do it, and I don't want to spend money on that. 

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Just completed this. Simple process using a piece of sheet metal and clamps as others have posted. I too turned the flapper towards the front of the truck. Thanks to all of those who posted and added pictures!

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After almost 2 weeks of driving with this mod, the only time I hear a concerning noise is when the truck auto-stops at a stop light, then re-starts. It sounds a little choked whenever that happens. 

 

Otherwise, loving the mod still. :thumbs:

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Can somebody please explain the purpose of this mod? Sound only? Or performance also? 

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My truck seems a lot faster after the mod. 

 

Oh... wait... that's because I'm mashing the gas pedal a lot more to hear the improved sound. :D

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this is mostly an aesthetic sound upgrade removing the restriction of the flapper valve may give you a tinny bit of performance at higher RPMs but I wouldn't count on much.

 

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Did mine a couple days ago.  I had some left over HVAC aluminum foil tape and taped up the "vents".  

Then for the flapper mod, I took about 4 1/2" piece of flexible metal strap and made a "U", with equal length's on all 3 sides, tightened it onto the outside of the flapper valve, turned it the direction in the pic, then tightened the inside with the hose clamps.  

I've driven it a few hundred miles and the tape is holding up fine, and with it being taped facing the inside of the truck, you can't see it from the wheel well.

Again, it's not going to make your truck set off car alarms...but does give you a nice little sound improvement for in my case, just left over items in my barn.

 

 

b4.jpg

flow.jpg

z.jpg

fromtheroad.jpg

HVACTAPE.jpg

tape.jpg

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7 hours ago, Cohocarl said:

Did mine a couple days ago.  I had some left over HVAC aluminum foil tape and taped up the "vents".  

Then for the flapper mod, I took about 4 1/2" piece of flexible metal strap and made a "U", with equal length's on all 3 sides, tightened it onto the outside of the flapper valve, turned it the direction in the pic, then tightened the inside with the hose clamps.  

I've driven it a few hundred miles and the tape is holding up fine, and with it being taped facing the inside of the truck, you can't see it from the wheel well.

Again, it's not going to make your truck set off car alarms...but does give you a nice little sound improvement for in my case, just left over items in my barn.

 

 

b4.jpg

flow.jpg

z.jpg

fromtheroad.jpg

HVACTAPE.jpg

tape.jpg

Nice setup and instructions 👍

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Posted (edited)

The weather played nice long enough for me to get this knocked out, this past Tuesday night.

Really a nice change in tone, not to mention the almost 2 mpg increase I've noticed.

This mod definitely ranks high on the Bang for the Buck list.

I used DEI aluminized tape and thin SS muffler repair pieces cut into 3x3 sections as well as 2 clamps per piece.

On the valve, I did exactly like Cohocarl suggested with a 4.5" long piece of flexible hanger strap and two clamps.

Take care around the drivers side tail pipe screen where it's close to the heat shield. The shield has a very sharp edge.

 

Here's the 1st cold start, bugs were getting rough.

 

 

20190723_201111.jpg

Edited by KEEPER OF SECRETS
added info
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Nice, KEEPER OF SECRETS! 

 

I feel like my MPG has gotten worse lately. I don’t at all think the exhaust hack is at fault, but it was coincidental that my MPG has been worse since I did it a few weeks ago. 

 

Mostly, I think it’s due to more stop and go traffic light 40mph and under city driving. 

 

I did avg about 20mpg over 120mi round trip on the interstate today doing 75mph avg. 👍🏼

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On 7/28/2019 at 8:38 PM, econometrics said:

I feel like my MPG has gotten worse lately. I don’t at all think the exhaust hack is at fault, but it was coincidental that my MPG has been worse since I did it a few weeks ago.

I haven't driven mine enough to have a valid before/after mpg, but I haven't noticed my mpg improving...but that could be due to several reasons.

We are moving our son up to college in a couple weeks which is a 400 mile trip each way.  Thought I'd remove flapper mod for the trip home to see if there's a notable difference.

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