Jump to content

Another Flapper Valve Question

70rsss
 Share

Recommended Posts

70rsss Enthusiast

70rsss

Posted
Posted

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?

  • 1 year later...
franktrusty Enthusiast

franktrusty

Posted
Posted

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. 

  • 8 months later...
WeGone Enthusiast

WeGone

Posted
Posted (edited)

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 by WeGone
  • 5 months later...
newdude Senior Enthusiast

newdude

Posted
Posted
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 Enthusiast

Tdola

Posted
Posted (edited)

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 by Tdola
Rob Mugs Enthusiast

Rob Mugs

Posted
Posted
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 Enthusiast

Tdola

Posted
Posted
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.

  • 2 weeks later...
Byrds8 Enthusiast

Byrds8

Posted
Posted

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • newdude
      Cold start Miss, oil in cylinder

      By newdude · Posted

      Its coolant disguised as oil.   TSB 20-NA-166 -  20-NA-166 1..3   "To inspect for this concern, add coolant dye to the system, run the engine through warm up, pressurize the cooling system after warming the engine to operating temperature (let the engine cool overnight) and inspect the suspect cylinder with a borescope for coolant dye evidence. At times it may be necessary to remove the head for inspection. If the head casting line is the concern, the intake port will be wet with a coolant oil mix"
    • asilverblazer
      Cold start Miss, oil in cylinder

      By asilverblazer · Posted

      Can you sample the pooled liquid, enough to confirm it is oil?   ...That its not fuel or coolant.   Also, make sure combustion gases aren't entering the cooling system.   Simply put, either oil being pushed up past the rings (this really isn't possible), oil leaking past the head gasket, oil leaking past the valve, oil entering through the intake air path. If none of this is likely - it may not be oil.   What could be likely is the fuel injector leaking down. A puddle of gas would still smoke and rough idle. (Same cylinder has the same problem after injector replacement?)   What is the crank time first thing in the morning, when the puddle would be present? Does it seem like the high pressure fuel pump needs an extra second or two to rebuild the pressure that injector 8 may have let bleed off? Check the fuel pressure via a scanner prior to starting the engine.    
    • Donstar
      Navigating senior years.

      By Donstar · Posted

      Good information!  I didn't know about the dementia aspect and asked for a general for my second knee. I'd heard that recovery room time is usually shorter with a general.   The anesthesiologist talked me out of it and I had the spinal.  Inconvenience and/or discomfort is a small price to pay for reduced risk!
    • garagerog
      Navigating senior years.

      By garagerog · Posted

      This is for those over 70 years of age contemplating joint replacement surgery involving general anesthesia. Even some 55 yrs. ago when I took my pharmacology class the dangers of developing dementia in the elderly that had general anesthesia were beginning to be recognized. Over the years there has been some refinement in the cautionary warnings, avoid general anesthesia if possible if you've had close to 10 priors, especially over the age of 70 and/or a family history of dementia. I'm not including the twilight anesthesia induced by propofol often used in cytoscopies or colonscopies. Seriously think about seeing a neurologist and undergo cognitive testing before proceeding if any of those criteria apply to you. Spinal anesthesia may be an option in some cases. I'm in the above camp and although I could use a new right knee, I get fidgety according to a prior orthopedic surgeon when the bone saw spools up or maybe it was the smell of saw blade meeting bone, anyhow I may have one general anesthesia left in me which I will pocket for now and I'm choosing mind over mobility, anyway where did I leave my damn cane!
    • GMCustomerService
      July 2026 upgrade push issues

      By GMCustomerService · Posted

      We understand your frustrations with your auto start/stop, fuel gauge and cruise control concerns since your latest update, @LarT-26. You mentioned getting repairs completed, however, have your concerns been resolved? If not, we would like to learn more so we may explore the best path of assistance moving forward alongside your local dealership. When you have a moment, please visit: https://s.gmc.com/support-request and complete the request form with all pertinent details. This will help us to better understand your concern and ensure that it is routed correctly. We will keep an eye out for your outreach.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...