Jump to content

Exhaust with no drone?


campbell45

Recommended Posts

Posted

I recently bought a RCSB with the 5.3. I was looking for just a little noise with out creating a lot of noise inside. I found a good deal on a MBRP 3" exhaust "slightly used" so I figured I'd give it a shot. I'm glad I did, hardest part of the install was removing the factory exhaust. The exhaust fits great, and the sound is perfect. Under acceleration, it's got a great roar to it, but at idle it's a pleasant low rumble that I can just barely hear while in the truck. On the highway, I can just barely hear it, no loud drone or noise at all (I've never heard my truck on the highway from outside the cab, so who knows or cares what everyone else hears). I couldn't be happier with it.

  • Replies 105
  • Created
  • Last Reply
Posted

With a fairly strong understanding of sound resonance, flow regimes and all that jazz, I looked into the flow mechanics of the GM Borla system and there IS significant effect from relocating the "flapper valve" upstream of the muffler. The stock muffler is actually fairly free flowing however, it creates turbulent or "dirty" flow downstream which the flapper valve helps to smooth out and is cleaned up by the resonator. Now, from what I can tell, and I used software that certainly wasn't designed for this application, but still similar, having the flapper valve upstream of an even MORE free flowing system helps to smooth the flow and control the velocity BEFORE it has a chance to become turbulent and create vibration, which in turn creates unwanted noise. Hence why Dynomax attempted to create a similar effect inside their VT muffler. I think I'm going to try an oval Magnaflow WITHOUT the resonator but moving the flapper valve upstream of the muffler. My goal is mimic the outcome of the GM Borla system. I want noise when I'm to the wood, wanna hear it idle, but don't want to hear a steady subwoofer racket on the freeway. I'm not overly worried about V4 mode as my truck is lifted 7" on 35's and, well, pretty much never sees V4 as a result. If anyone would like to suggest a Magnaflow that would be best, I'll give it a try and report back and try and use instrumentation during a video to produce real, measurable outcomes. I will be installing V-band flanges up and downstream of the muffler so I can install different mufflers to experiment. This venture will be subsidized by a local outfitter who wishes to be able to better tailor what its customers get. Meaning, they get a LOT of guys/gals coming through their doors every day asking for the same things as many of you, myself included, but don't want to shell out $1k+ for a catback system. So, we're going to try these theories out with about 4-5 different mufflers and record the results on video as well as with sound metering equipment for some unbiased results.

 

So I am trying to mimic a Borla GM exhaust as well. The muffler I picked out is the Borla ProXS 40359. This is suggested for the 2014 5.3lt on Borla's website. Would love to hear the difference of moving the flapper before the muffler. My plan was to just do a muffler swap first then delete the resonator after if it was too quiet. Was planning on leaving the valve no matter what as right now I have it pinned open anyway. That way I can pull the pin on the valve when I'm towing my camper.

 

Please let us know if you made any headway!

Thanks,

Jon

  • 11 months later...
Posted

Reviving an old thread... I have a 6.2L..tried the muffler delete and it sounds good but too loud for me and the neighborhood. Resonator and flapper are still installed but the flapper rattles and I have had to clamp open. I have 3.5 inch exhaust. What 22" Magna flow exhaust can I get that will fit... I need a sound reduction but still want some rumble (assuming with sound reduction v4 will decrease as well)... Any help is appreciated... Planning to remove resonator and flapper if find the right muffler. I have an AFE Momentum GT CAI installed and am sure this has added to the sound increase as well. Thanks in advance.

 

Sent from my Note 5 using Tapatalk

Posted

I just found a GM Performance exhaust tonight while trolling around on the net. I didn't get a chance to research it or know anything about it. Maybe you might want to look into it or maybe someone here knows.

GM part # 23462043.

I'm sort of looking for another exhaust system. My Corsa is loud upon startup and I'm sure about 5 of my closest neighbors don't appreciate it, not to mention I can't touch the accelerator until I get out of my gated community. I really don't want to put the stock exhaust back on it BC it's just as quiet as a Prius. The Corsa is great on the freeway for those times when you get a sleeper in the fast lane holding up the flow of traffic. When they finally move over I roar right past them and wake 'em up!

  • 2 months later...
Posted

Reviving an old thread... I have a 6.2L..tried the muffler delete and it sounds good but too loud for me and the neighborhood. Resonator and flapper are still installed but the flapper rattles and I have had to clamp open. I have 3.5 inch exhaust. What 22" Magna flow exhaust can I get that will fit... I need a sound reduction but still want some rumble (assuming with sound reduction v4 will decrease as well)... Any help is appreciated... Planning to remove resonator and flapper if find the right muffler. I have an AFE Momentum GT CAI installed and am sure this has added to the sound increase as well. Thanks in advance.

 

Sent from my Note 5 using Tapatalk

 

 

Did you get a muffler installed?

 

https://www.magnaflow.com/products?partNumber=12909#modal-compatiblevehicles

Posted
Yes. 12909 Magnaflow.. I am happy with the results. Very little sound when cruising. Not super loud but better than stock on start up. When I give it the gas it sounds great. Super satisfied. I found since I did both the afe and the muffler the system seems way more responsive and is much more pleasurable to drive.

 

Sent from my Note 5 using Tapatalk

  • 2 weeks later...
Posted

Yes. 12909 Magnaflow.. I am happy with the results. Very little sound when cruising. Not super loud but better than stock on start up. When I give it the gas it sounds great. Super satisfied. I found since I did both the afe and the muffler the system seems way more responsive and is much more pleasurable to drive.

 

Sent from my Note 5 using Tapatalk

Same muffler here, all 3.5" tubing, no res, no flapper, 4.5" tip I think it sounds fantastic.

I also tow a 9000# camper long distance, not annoying in the least even towing.

 

I also believe there is an increase in response, I have an intake tube as well.

 

Did you replace entire tail? or leave the restrictions in place?......lol

Posted

Same muffler here, all 3.5" tubing, no res, no flapper, 4.5" tip I think it sounds fantastic.

I also tow a 9000# camper long distance, not annoying in the least even towing.

 

I also believe there is an increase in response, I have an intake tube as well.

 

Did you replace entire tail? or leave the restrictions in place?......lol

I replaced the entire tail and installed and AFE cold air Intake. Response has been improved to me.

 

Sent from my SM-N920V using Tapatalk

Posted

I replaced the entire tail and installed and AFE cold air Intake. Response has been improved to me.

 

Sent from my SM-N920V using Tapatalk

Agreed!

IMG 20161110 133844619 HDR[1]

tail 2.1

IMG 20161017 181311126

 

  • 5 months later...
Posted

I think i am now committing to the Magnaflow 12909 to replace the stock muffler and flapper valve but leaving the resonator on. i was also planning on installing an Airaid Jr MIT with an AFE dry filter, keeping the stock Intake box. Does anyone have the part number for the MIT for a 2017 Sierra 6.2?

  • 3 weeks later...
Posted

I just found a GM Performance exhaust tonight while trolling around on the net. I didn't get a chance to research it or know anything about it. Maybe you might want to look into it or maybe someone here knows.

GM part # 23462043.

I'm sort of looking for another exhaust system. My Corsa is loud upon startup and I'm sure about 5 of my closest neighbors don't appreciate it, not to mention I can't touch the accelerator until I get out of my gated community. I really don't want to put the stock exhaust back on it BC it's just as quiet as a Prius. The Corsa is great on the freeway for those times when you get a sleeper in the fast lane holding up the flow of traffic. When they finally move over I roar right past them and wake 'em up!

 

Do you want to sell the corsa?

 

 

  • 1 year later...

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,902
    Total Members
    8,960
    Most Online
    whenindoubtuseahammer
    Newest Member
    whenindoubtuseahammer
    Joined
  • Who's Online   0 Members, 0 Anonymous, 289 Guests (See full list)

    • There are no registered users currently online
  • Latest Articles

  • Posts

    • are there any codes? with lots of rust, perhaps disconnect/clean both sides of the connection/examine cable ends (the wires) for corrosion going into the sheath & replace if necessary/reconnect ALL the power AND ground cables between the battery, engine, frame, cab, fuse box and starter charm.li (website) has a no-start diagnostic procedure you can work through to get it working.
    • Its no wonder you've gravitated to the oil types and brands you have in later years after trying certain brands and one being a specialty oil or at least very hard to come by up here and the other would have been a commonly found oil of the era and the vastly different outcomes as a result to using the vehicles in question the same distance for an OCI . It shows what marketing hype can do without actually having the product to back up the claims and that is no different now with the insane claims that are written on the side of a bottle of oil from some of the off the shelf oils.    What has surprised me and I was already finding this out before I bought my truck with the GDI engine, that this newer fancy technology that seemingly would suggest better fuel economy/emissions with this high pressure spray of fuel is not in reality kind at all to the engine or at least the oils life. Yet they insist on claiming long OCI with this technology just like they did with the port or similar type fuel injection systems when in reality its a step back in oil life to have a GDI system.    I think the mistake your making Grumpy is that your not sending your samples to Blackstone and getting the feel good glowing report that you can run it another 1000 or more miles and then send another sample where they say run it yet another 1000 miles and on and on it goes until your sending in something that looks a lot like road tar and then they may suggest you change your oil within the next 1000 miles 😆
    • I am guessing that engines of that design back then had a better ability to be abused and survive longer than a new design engine with the long timing chain and the overhead cams and phasers etc. But I would never guess that an engine could go that far and not fail spectacularly or at least die a slow death. 
    • In the 80's 90's I'd run Honda's 7,500 miles between changes using Red Line HP 5W20 and do it for hundreds of thousands of miles with issues. Back in the day it was an SAE 20 with the HTHS of a SAE 30 and SN add load. It was also very polar. Oxidation VOA was over 120. Besides those motors were SPFI and lean burn tech. I could have likely run it longer but never did.    We had a Toyota bought new I ran on Pennzoil's latest and greatest synthetic of the day with "Penthane". A made up word for a very low dose of PAO. Tried 7,500 mile OCI's in that Group III/VI chemistry and the rings tapped out at 90K. Rocker box wasn't as bad as the one Punch put up but it wasn't good either. Also a SPFI motor.    I'm around 3,750 across the board on these GDI monsters and the oil it tapped out by then usually on TBN/TAN crossover and color. Red Line HP Euro.    The AMSOIL SS brochures tell you to follow the OEM values for the service class but that it can be run up to 25K if monitored. I can't imagine what motor could go that distance and not tap out. I've never owned one.    Yes, I know. Lot's of people do. I'm just not going to be one of them. 
    • I knew a guy in the early 80's that bought a new Monte Carlo and ran it a 100,000 miles without ever changing the filter or the oil. Just kept adding. It looked like that inside.     
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...