To resonate or not to resonate that is the question....

[Dravec]

Good news is it ain't rusty. Somewhere on there is a part number.

 

[kenh]

Probably on the top side! Haha

 

[Texasdeere]

The old pancake cats used to really knock the sound levels down on the earlier trucks with the Flowmaster type mufflers. With no cat, headers and a single performance muffler it will make some noise. I would try a large resonator where the cat would normally go. It will help some. I believe a straight through Magnaflow up stream of your existing muffler (where the cat would normally be) would take the sound down even more. Vibrant makes some nice straight through resonator mini mufflers that would work if space is a problem.

 

[b454rat]

I need resonators on my Tahoe. I put a 3” borla xr1 with no cats and is LOUD!!! I think cause it resonates in the cabin more than outside. I have a cat back off 2020 chevy, has a single out the muffler but then splits to duals over the axle. But it has 2 smallish resonators before the dumps, might put them where the cats would go n see if it tones it down.

 

[Zerio29]

A resonator will more than likely help a little with the low end drone. I used a straight through glass-pack style muffler and it deadened a lot of the drone but was still open enough to scream when you really open it up. but like syndicate said, it will change the overall sound of the exhaust and there's more to it than just muffler and resonator choice. I've also known rolled tips to deaden the sound just a hair... not much, but enough to tell.

 

[studigggs]

Can you recreate the sound at a stand-still by holding RPMs high? If not, I would think a speed dependant drone/hum would be more rear end or drivetrain related.

 

[b454rat]

Its definitely because of the muffler. It had a stock muffler before, just replaced it with this and the tailpipe. The Borla is the round version, straight thru. Higher RPMs it sounds great, I'm loud but I'm inside and can't really hear it. (its still cold up here so windows are up lol). Now that it's getting warmer and my driveway is cleared of snow/ice, I'll peak under and see if there's a straight shot to put the resonators. I ordered a Dynomax Ulatrflow, maybe that tone it down too.

 

[moremudd]

I know this is old tech as far as eliminating exhaust drone but it works really good and does not alter the sound noticeably . Google " Capped Helmholtz chamber " anti drone .
an example . https://www.e46fanatics.com/threads/custom-exhaust-for-my-e61-wagon-pics-videos-detials.1088541/

 

[618 Syndicate]

Can you recreate the sound at a stand-still by holding RPMs high? If not, I would think a speed dependant drone/hum would be more rear end or drivetrain related.

That won't work because the motor will sound different under a load.

 

[618 Syndicate]

A resonator will more than likely help a little with the low end drone. I used a straight through glass-pack style muffler and it deadened a lot of the drone but was still open enough to scream when you really open it up. but like syndicate said, it will change the overall sound of the exhaust and there's more to it than just muffler and resonator choice. I've also known rolled tips to deaden the sound just a hair... not much, but enough to tell.

Yup, rolled tips vs straight or slash cut will change the sound, as will single or dual tip choices. Also where in the system your can(s) and resonator(s)are located.
The other thing to keep in mind is that exhaust sound is highly subjective. Around here many folks will leave the cats in place and run dual slash cuts out the back or sides after the rear axle, and swear it sounds great. To me that flat farting loud sound is awful, but I see guys every day who paid money to have a truck sound like that....