leave flapper valve or not

[tbarn]

6.2 has noise cancelling does it not? maybe that's why you don't hear it.

[Centex14]

What muffler you have?
You wont hear it unless its in V4 mode and flapper can move freely. 

GM Borla. Had the v4 mode for two weeks before I tuned it. Never heard it.


2014 z71 LTZ
Volant Intake
Borla Exhaust
Diablo
Bilstein 5100
Rough Country Level

[J_Mas6.2]

2 hours ago, GMC_SD_Ult_16 said:

I removed oem muffler, resonator, and valve and replaced with a 12909 Magnaflow on my 6.2L. Been super happy with sound and don't notice the annoying sounds described by others.

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This was the one i was going to go with, and last minute changed my mind and ordered a borla xr-1 sportsman p/n 40946.  planning to leave the resonator on and removing the flapper valve. Hoping this will add a nice little rumble to it.  planning on having my tune updated as well.

[GMC_SD_Ult_16]

6.2 has noise cancelling does it not? maybe that's why you don't hear it.

My noise cancelling is off due to my subwoofer install. So that is not it for me.

I have ridden around with out the system on as well to hear the sound. It produces the noise, to me, that it should for a 6.2L. You can tell when it is in v4 slightly but for me it is not much different than it sounded stock with light throttle and more aggressive with throttle near & over 2k rpm.

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[Ed S]

I put a complete Borla cat back system on my 14 Sierra 5.3. System eliminates the flapper valve. Sounds great except when it goes into V4 mode. Borla claims absolutely no drone at any speed or rpm. Not true. Good luck to anyone that eliminates that flapper valve.

[Jose d]

I have a 2015 Silverado 1500 5.3 removed muffler and resonator and “flapper” now it’s making a ticking noise what do you think it could be can someone help it’s driving me crazy had a flowmaster super ten single in dual out with turn downs 

[Ozer]

9 hours ago, Jose d said:

I have a 2015 Silverado 1500 5.3 removed muffler and resonator and “flapper” now it’s making a ticking noise what do you think it could be can someone help it’s driving me crazy had a flowmaster super ten single in dual out with turn downs 

Ticking sound could be part of the exhaust hitting the frame. Check where the flex pipe goes over the frame, its a very tight space, if they didnt align it right it could be the issue.

[Isaiah2017]

On 11/9/2018 at 10:38 AM, MN1(SW) said:

I removed my muffler and the valve and just welded a piece of pipe in their place. It sounded great to me and V4 really wasn't that noticeable. Not to me at least. If push comes to shove, you can always just leave it and lock it in the open position with some with some wire or something. If you don't like it, you can always close it. 

Will deleting the valve throw a code on dash ? 

[Isaiah2017]

Will deleting valve throw a code ? Plan to tune out when tuner comes in 

[reardiff]

While we're on the topic... is there any noticable difference  in performance, airflow, backpressure, MPG, etc.. with the flapper?  One would think anything inside the exhaust like this would impeed airflow.  

So other than sound, any benefits of removing it completely or forcing it open?  

[steelerdude15]

10 hours ago, Isaiah2017 said:

Will deleting valve throw a code ? Plan to tune out when tuner comes in 

It won’t.

[16LT4]

One of the main reasons I put a new catback system on my truck was to delete the flapper valve and its restriction; even wide open, the valve is a considerable bottle-neck to flow, along with introducing turbulence and friction to the exhaust flow.  For years, I'd been annoyed with the squeak every time the engine switched V8-V4 and back, and it got to the point where the valve was freezing shut, literally choking the engine and resulting in no power.