Another Flapper Valve Question

[70rsss]

Has anyone just cut out the two 6.2 exhaust flapper vales and left everything else stock? I have two fast and loud cars I don’t need a semi fast and loud truck. I would love to pick up power just not noise….. Just not sure if eliminating the valve would pick up HP?

[BigBlueLB756]

No.

[HistoryTeacher2020]

Get rid of it. 

[franktrusty]

I'm thinking of doing that, and getting a pulsar unit to keep it in v8 all the time. I actually like how my 6.2 sounds with the factory muffler...

[204Denali]

I do not see you picking up an hp gains doing that mod

[franktrusty]

If/when i do there's a dyno shop close by to get before/after.  The flappers do seem to restrict the exhaust slightly because the don't close flush... If it does  flow well enough with them in, then I agree i've wasted $50. 

[HighCountry MP]

did you take them out and how does it sound . im wanting to try that 

[WeGone]

I only have 1 and it is clamped open, not much change in sound if any except at idle. If you watch its operation as the motor warms up it does close some but opens again as you increase throttle. It appears to open  completely at high idle during start/warm up than slowly closes as idle rpms decrease.

Edited September 13, 2021 by WeGone

[Tdola]

Does the Check Engine Light come on once the flapper is removed? 

[newdude]

9 hours ago, Tdola said:

Does the Check Engine Light come on once the flapper is removed? 

 

 

No.  No electricals are connected to it. 

[Tdola]

I’ll be installing a Corsa Cat Back exhaust on my 2020 5.3 Crew Cab Short Bed Silverado 1500.  So, where is the flapper valve located and would I be able to cut it out and have enough piping with my Corsa that I can slip the Corsa over that location where I’d be cutting the flapper valve out or would I need to add in new piping where I cut the flapper valve out of and then install the Corsa exhaust?  

Edited March 11, 2022 by Tdola

[Rob Mugs]

1 hour ago, Tdola said:

I’ll be installing a Corsa Cat Back exhaust on my 2020 5.3 Crew Cab Short Bed Silverado 1500.  So, where is the flapper valve located and would I be able to cut it out and have enough piping with my Corsa that I can slip the Corsa over that location where I’d be cutting the flapper valve out or would I need to add in new piping where I cut the flapper valve out of and then install the Corsa exhaust?  

A catback will remove the flapper entirely.  On my 6.2, it's on the passenger side, around the backdoor area.  It'll have a square bolt with a spring behind it IIRC.  I chopped mine out early on

[Tdola]

31 minutes ago, Rob Mugs said:

A catback will remove the flapper entirely.  On my 6.2, it's on the passenger side, around the backdoor area.  It'll have a square bolt with a spring behind it IIRC.  I chopped mine out early on

Thank you for the info.

[Byrds8]

If you remove the flapper and leave DFM on, doesnt it sound like a helicopter? I plan on leaving DFM on. I used my neighbors Pulsar to see how I would like it but MPG dropped by 3ish. With my commute everyday, that is just a no go.