Jump to content

Recommended Posts

Posted

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


Sent from my iPhone using Tapatalk

Posted
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


Sent from my iPhone using Tapatalk

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

Posted

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.

Sent from my Pixel 2 using Tapatalk

Posted
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.

Sent from my Pixel 2 using Tapatalk
 

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. 

Posted

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!

  • Like 2
Posted

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:

Posted

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

Posted

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

  • Haha 2
Posted

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.

 

Sent from my Pixel 2 using Tapatalk

 

 

 

 

Posted (edited)

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.

 

**UPDATE Noticed tonight (9/24/19) that most of my foil tape patches have blown off.  Guessing too much heat for the adhesive on the foil tape.

 

b4.jpg

flow.jpg

z.jpg

fromtheroad.jpg

HVACTAPE.jpg

tape.jpg

Edited by Cohocarl
  • Like 1
Posted
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 ?

  • 2 weeks later...
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
  • Like 1
Posted

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. ??

Posted
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.

  • Like 1

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

  • Latest Articles

  • Posts

    • Monday looks like a good day for the dealer to test an ac issue. Hopefully it all turns out good.
    • Paid $2.72 for E85 today.
    • Welcome back! No, it definitely doesn't pass the sniff test. Even "ceasefire" needs an alternative definition these days.    $5.29 at Kroger today
    • That makes sense, and I think you are describing the real product problem. Capturing data is the easy part. If the owner or technician has to manually dig through five minutes of millisecond-level logs, the product has already failed. The device would be at the ECM harness, not at the OBD port, so I agree that data retrieval and event marking need to be thought through carefully. The way I am thinking about the architecture is: The recorder itself should not depend on a phone, app, Bluetooth, Wi-Fi, or cloud connection to capture the event. It should always keep a local rolling buffer and lock the event locally. A button, phone app, or small cabin device would only act as an event marker. If the driver feels a stumble and presses the button 10–30 seconds later, the pre-buffer has to already contain the useful data. For data retrieval, the practical options would be a sealed service USB lead, Wi-Fi download, or a phone/cabin companion device. I would not expect the owner to remove the ECM-side module or work with raw files directly. The cloud or AI side would be for interpretation, not for capturing the event. The truck may have no connection when the issue happens, so the evidence has to be saved locally first. After that, cloud processing could help decode the data, compare it against baselines, and generate a readable report. For the first version, I would keep the automatic triggers conservative and objective: driver event marker bus-off error passive voltage drop / brownout device reset FIFO or queue overflow a normally periodic message disappearing side-to-side communication mismatch, if the topology supports that For “learning normal,” I agree with your point, but I would not want to overclaim it as automatic root-cause diagnosis at first. A realistic first step would be learned baseline comparison for that specific vehicle and operating condition. For example, a value would only be compared against similar conditions: RPM range load / MAP throttle position gear / vehicle speed coolant and oil temperature battery voltage AFM/DFM state, if decoded and validated Then the report could flag things like: this periodic message disappeared compared with its normal timing this value deviated from this vehicle’s normal range under similar conditions the same abnormal pattern repeated after the same type of event the anomaly occurred together with voltage, oil-pressure, misfire, or communication changes But I would still call that “abnormal pattern detected,” not “replace this part,” unless there is enough validated repair data behind it. So the intended product would not be “here is a huge log.” It would need to be an event package: what triggered the capture how much pre/post data was preserved what changed before and after the event whether the device itself reset, overflowed, or saw a bus error selected graphs around the event raw data only as supporting evidence From your perspective, what would make this kind of report useful instead of just another datalog? For example: What are the top 5 parameters or events you would want highlighted first? Would you trust a learned baseline for that specific vehicle, or would you prefer fixed thresholds? How much false-positive flagging would be acceptable before you stopped looking at the reports? What would a one-page report need to show for an independent shop to take it seriously? For misfire, AFM/DFM, oil pressure, or U-code complaints, what would you want the tool to flag automatically?
    • 2024 Silverado 2500 HD LTZ grille no camera Parts list   84603331 84913656 84913657 84913654 84913655 84911567 84911568 85646092 85646093 85797921 85797922   11570637  x10-15   grille/bumper bolts 11546500  x10      grille clips 11571006  x10      push/retainer clips 11546454  x6       nut retainers 11611609  x6       M5 bolts 11610700  x6       molding/trim retainers
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...