Magnaflow universal mufflers, looking for explanation on size impact on sound

[A Stupid Turtle]

I'm looking into universal mufflers by magnaflow, they will be the round style with 2.25 inlet and outlet.
What I do not have a grasp of is how the diameter of the muffler affects the sound.

The application will be on a 4.2l C5 S6 with deleting center resonator, replacing with these mufflers, and deleting rear mufflers, and adding 2.25 to 4 inch tips.

The goal is the most burble, with no-minimal rasp, moderate drone to be expected.
My assumption is that the largest diameter would help achieve this, but I guess I really have no clue or reasoning for this...

Thanks,

Tim

[MagnaFlow]

I'm looking into universal mufflers by magnaflow, they will be the round style with 2.25 inlet and outlet.
What I do not have a grasp of is how the diameter of the muffler affects the sound.

The application will be on a 4.2l C5 S6 with deleting center resonator, replacing with these mufflers, and deleting rear mufflers, and adding 2.25 to 4 inch tips.

The goal is the most burble, with no-minimal rasp, moderate drone to be expected.
My assumption is that the largest diameter would help achieve this, but I guess I really have no clue or reasoning for this...

Thanks,

Tim

Simply put: More muffler diameter will mean more noise absorption.

Muffler body diameter shouldn't change the tone significantly since the straight-through core is still going to be 2.25". The biggest difference will be volume with more diameter eliminating more sound, which typically includes a bit of the rasp and the drone.

[aysix]

wtf?! first time i've seen a magnaflow vendor on here...well that's cool

[ChicagosPhantom]

lol...thinking the sam thing.
Let's see how they keep with all the Q...
Can't wait to install my new set up,just can't wait.

[ChicagosPhantom]

I'm looking into universal mufflers by magnaflow, they will be the round style with 2.25 inlet and outlet.
What I do not have a grasp of is how the diameter of the muffler affects the sound.

The application will be on a 4.2l C5 S6 with deleting center resonator, replacing with these mufflers, and deleting rear mufflers, and adding 2.25 to 4 inch tips.

The goal is the most burble, with no-minimal rasp, moderate drone to be expected.
My assumption is that the largest diameter would help achieve this, but I guess I really have no clue or reasoning for this...

Thanks,

Tim

I have the same set up on my allroad,but its 2.7T so it's not comparable to that V8...but you're definitely can expect more throathier and deeper sound.Those mufflers just bring what you're talking about.No rasp,little bit of drone (I don't mind it,but wifey noticed it right away on first ride),exhaust note is so intoxicating.I just love it.Best bang for a buck.My mufflers are 14" if I remember correctly.Go for it...

[A Stupid Turtle]

Simply put: More muffler diameter will mean more noise absorption.

Muffler body diameter shouldn't change the tone significantly since the straight-through core is still going to be 2.25". The biggest difference will be volume with more diameter eliminating more sound, which typically includes a bit of the rasp and the drone.

Thank you; I sent you folks a 'message' (email - [email protected]) with a few other questions, any help greatly appreciated.

Any idea of how much decibel would be affected from a 4 inch diameter to a 6 inch diameter if that was the only difference?

Also, what would the impact on sound be if the mufflers replaced the factory resonator position and had about 2 and a half feet of piping (2.25") versus mufflers being placed within a foot of the end/tip? Looking for impact on decibel and frequency purely.

And lastly, I am looking into you folks 2.25 to 4 inch tips. Question being what is the impact again on frequency/decibel if the tip is 5 inches long versus the foot long? As well as do you offer the part #35173 in a non resonated option? What is the purpose for a "resonated tip"? My thought being purely lessen decibel rating but it seems to affect more than that. The air itself coming out of the tip sounds much more violent/agitated, almost as if this gives me a grasp on if the muffler has more pipe after it, it allows for the resonance of tone created to increase due to having an extended length before escaping to atmospheric pressure.

Sorry for the questions, my girlfriends and audiologist, and I'm an engineer... explanation being, she can't help me with my questions, so we emailed a prof. Of hers haha!

[A Stupid Turtle]

I apologize but I can't seem to understand that the larger diameter with more sound absorption induces more rasp? Understanding in a minimal aspect but also not sure as to how?

Is there a preference as to where you would suggest I purchase your products through?

If your labs where closer I'd love to check it all out!

[MagnaFlow]

wtf?! first time i've seen a magnaflow vendor on here...well that's cool

Yep, we're here and trying to keep up.

Thank you; I sent you folks a 'message' (email - [email protected]) with a few other questions, any help greatly appreciated.

Any idea of how much decibel would be affected from a 4 inch diameter to a 6 inch diameter if that was the only difference?

Also, what would the impact on sound be if the mufflers replaced the factory resonator position and had about 2 and a half feet of piping (2.25") versus mufflers being placed within a foot of the end/tip? Looking for impact on decibel and frequency purely.

And lastly, I am looking into you folks 2.25 to 4 inch tips. Question being what is the impact again on frequency/decibel if the tip is 5 inches long versus the foot long? As well as do you offer the part #35173 in a non resonated option? What is the purpose for a "resonated tip"? My thought being purely lessen decibel rating but it seems to affect more than that. The air itself coming out of the tip sounds much more violent/agitated, almost as if this gives me a grasp on if the muffler has more pipe after it, it allows for the resonance of tone created to increase due to having an extended length before escaping to atmospheric pressure.

Sorry for the questions, my girlfriends and audiologist, and I'm an engineer... explanation being, she can't help me with my questions, so we emailed a prof. Of hers haha!

I'll try to tackle these the best that I can.

Decibel effect going from 4" diameter to 6" diameter...if the 2.25" core is still the same, it's a math problem using volumes of a cylinder then. Since the volume is (pi)(r^2)(h) and the core is the same size, the difference functionally is going to be (4^2) to (6^2). Or a 6" muffler should theoretically have around twice the sound absorption of a 4" round muffler. You're an engineer, so you know that doesn't mean it will halve the decibels or make it half as loud since decibels are a logarithmic value. The basic takeaway here is that it's a pretty big difference in volume. :)

Positioning...that's a good question that I don't have an answer for at hand. It's worth a call to our Tech Line (1-800)-990-0905 to chat that one over.

The tips ...when you say "resonated tip," do you just mean double-walled? That's more of a durability thing than anything so that the stainless steel inner wall insulates from the high temp. The tip length shouldn't make a massive difference in the tone relative to things like changing the muffler size or the whole exhaust diameter.

Larger diameter/rasp...I think I was unclear there with my words. What I meant to say was "More muffler diameter means more sound absorption, which includes absorbing a bit of the rasp and the drone." Sorry for my poor choice of words; those writing classes I took many years ago have clearly long ago escaped.

Purchasing MagnaFlow products...You can find authorized local brick-and-mortar dealers on our site here or authorized online dealers here.

As for our email inbox...if you've got a bunch of questions, the phone line above is probably still our best option for timeliness and completeness of answer. I don't work in the tech line myself, but if you're not happy with the answers from the tech line, shoot me a PM and I can usually get an answer a bit quicker than the general email address on the MF site. I'll forward all this on, by the way, to see if I can get more complete answers.

[A Stupid Turtle]

If you do get the chance to inquire about the positioning question that would be appreciated; I am looking out about a month before I do anything as the vehicle is currently under the knife for torque converter/transmission and paint/body related components

The resonated tip question I believe stemmed from me believing that some of these tips (either #35173/#35714) having some form of perforations/baffles to alter db/tone. I am most likely wrong as when talking to my father I remember lots of talk of baffles being removed from his marauder tips therefore them no longer being resonators, so it seems my idea of what a "resonated tip" is may not be proper.

If there has been a test between the db difference of the universal mufflers (in terms of 4" v 6"), I'd love to have a percentage of db difference, or simply the difference of sound intensity emitted. Understanding testing was most likely a motor with XXX displacement (not comparable to European 4.2l) that the numbers won't be exact, but will hopefully give an idea or ratio of one to the other size.

Thanks again!