Quieter muffler for LS Motor

[Shes Mad]

I hate the muffler that the exhaust guy put on my 60 with an LM7 motor. Has a real annoying mid RPM cackle under power. 2-2500 RPM. Sounds good at WOT above 3,000 RPM.

I don't know the brand. I have hookers on my Camaro, and they are not quiet, but they don't cackle. Anybody have any sound bites of theirs under power? I'll try to get an audio driving it if I can do it without a lot of wind noise. It isn't bad revving while in park, only while driving.

Will a resonator cure the cackle?

 

[gregnash]

Could be a couple different things but more than likely the guy installed an open baffle type muffler (see welded muffler). I did quite a bit of sound research when I dropped a new muffler on my 60s 2F and found that my welded is much quieter when I have a full extension of "exhaust pipe" after the muffler. Right now it is broken off about 2' from the muffler where as before it has a good 4' of pipe and the mid rpm resonance can get annoying.

With that said, look for Quiet Flow type mufflers or "Turbo Style" mufflers. You want something that has multiple routings inside the muffler NOT just a few baffles..
This is a Turbo Style muffler, the main drawback is that it is more restrictive than the other types and thus will sap some power..

This is the particular muffler that I have and do not find it to be overly droney or crackly when the full exhaust pipe is installed.

 

[Shes Mad]

Pretty sure mine is the TURBO style you have listed first. My Camaro is the second style. I put a longer magna flow on it first, and it was HORRIBLE.

I might have to buy a stock muffler like was on the donor vehicle and try that out. Muffler is in front of the axle in the stock position, with tailpipe all the way out the back, so I think that is long enough

 

[SteveH]

Go back to your exhaust guy and tell him to get it right (unless you specifically asked for this muffler yourself).

 

[gregnash]

Definitely talk with you shop to see what they installed so that you know exactly what it is/was. Not all mufflers sound the same so it could be a turbo style muffler but of some off-brand that sounds like crap. I know there are a few guys on here who have replaced their mufflers with the Quiet Flow Walkers (i think its walker) and like them a lot.

 

[Lowrecoil30]

I installed a Magnaflow 11236 on my 5.3 swap and it is pretty quite. Not drone from what I can tell so far.

MagnaFlow Performance Mufflers 11236

 

[Shes Mad]

the Magnaflow I put on was a 13236. Not good result for me.

Im going to try an OEM muffler like the donor truck had on it

 

[gregnash]

the Magnaflow I put on was a 13236. Not good result for me.

Im going to try an OEM muffler like the donor truck had on it

See looking at the magnaflow website that muffler is kinda a hybrid muffler. It has both chambers like a baffled or welded muffler but also has perforated tubing link a turbo style. Probably like that so it has a bit more grunt and rumble than a pure turbo style but not as much as a full welded/baffled muffler.
4 x 9 OVAL 13236
vs.
4 x 9 OVAL 11236 (which is definitely a more traditional turbo style)

Also, dont know if this will help much but here is my little thread I did when I replaced the exhaust about this time last year. The video is actually the exhaust terminating just over the axle pointing at the ground. I had built an extension with a section of flex-tube to have it completely terminate behind the rear wheel at the fender however, that recently rusted out and the pipe dropped off. I need to actually reweld everything in coated steel instead of using the dumb flex pipe. I knew that would be a temporary fix but with all the weather/wet we had this last winter it rusted through that in no time.
FJ60/62 Aftermarket Exhaust - More Theorycraft
And this is the muffler I used... was like $55 from Amazon if I remember correctly.
Thrush® Welded Muffler

 

[zipper]

Maybe do what Lexus did with the lx470, and hang weights off of it to counter the resonance.

 

[Dozer18]

I put a Walker Quiet Flow S/S on my LS Swap, and I'm very happy with it. However, I gave it to the muffler shop when they built my exhaust, so they were able to fit the pipes to the muffler as far as placement.

Here's a link to the one I used: https://www.amazon.com/gp/product/B000JZYT9E/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1

 

[cruiser enthuiser]

You could add a resonator. I didn't care for the volume and general rowdiness of my muffler. I added one and I like the sound a lot now; still throaty when under throttle but not raspy like it used to be.


-Ed

 

[Shes Mad]

Thanks for all your help. I'll post progress!

 

[MANUCHAO]

Your local muffler shop could give you good advise on this... i only hear mine when i downshift... other times is really quiet....i know mine is a magnaflow, but dont know the model number..

 

[AggiePE]

I got the biggest muffler that magnaflow made (model #12588) and it has a nice rumble to it. not too loud unless i really get in it on the road when I have to put a mustang in its place!

 

[zipper]

Not too far off topic, but this is a really good question. Even when I put a new muffler on my 2f, I told the shop to put the biggest quietest one they had on, and it still sounded like crap in the truck. OEM never seems to be an issue with any brand, though. How hard is it to make a muffler???

 

[vipergrhd]

.

This should do the job.

 

[vipergrhd]

I just had my head unglued and I remember someone here actually bought a factory exhaust system after the Catalyst and the price was not bad.

 

[Shes Mad]

The muffler is a dynomax 17733 superturbo. If you go to their site, It had a cackle just like the start up on their sound bite, with it getting more pronounced under load.

I added a vibrant 1793 resonator. It not only took out the cackle, but it smoothed all the tones. I tried the shorter 1792, but it didn't help much. I tried all 4 vibrant makes, and just slipped them over the tailpipe to compare the sound. 1793 definitely the best.

Now it has a nice low note at idle and acceleration, and is super quiet at highway speed.

 

[dogfishlake]

I vote Walker Quietflow. I have one on my 80 with SC, header and 3" exhaust and it is the best of 3 attempts. Still rumbles a bit bit but not too much. Also added a small stainless resonator as an exhaust tip out behind the rear tire.

My 60 is just a stocker exhaust behind the 2f