Magnaflow Muffler Sound/Note

mikedsilva · 03-02-2025, 08:33 PM

Looking to have a quieter muffler made for me here in Aus.
Currently I have a choice of either a Zork or a 3inch Vibrant Ultra Quiet Resonator.

The Zork has a nice note (raspy) but the volume is a little too high.
The vibrant has lower volume but the note is not as nice.

I've seen some pics of the double Magnaflow system that Turbokraft use for some of their clients.. would anyone have video links to that system?

I'm contemplating having something similar made. Maybe using 2 of the Vibrant utra quiet mufflers in series.. not sure.

I notice that the mufflers that have chambers without any packing, seem to produce the classic raspy sound that the 911 engines are famous for. But once you add packing they tend to lose that raspy note.

this is my current Vibrant muffler setup below.

Or would something like the magnaflow 14210 work albeit with smaller pipe diameter?

RarlyL8 · RarlyL8's Garage

How quiet does it need to be?
Our Street mufflers are not what I would consider loud, about twice the dB level of stock. Important part is to retain a straight through pathway as turbos don't like baffling or chambers.

Tug68 · 03-03-2025, 02:36 PM

I highly recommend Brian’s set up. They sound awesome and the build and material is second to none!

Longboarder · 03-05-2025, 03:56 PM

Quote:

Originally Posted by RarlyL8

I use Brian's headers and Hoonigan muffler as well. Because I have to pass smog and drive in my town that has a noise ordinance (got to love Laguna Beach, California), the tube just below the license plate in the pic above is modular and Brian provided me with a catalyst which bolts right in. The cat quiets it down a lot and the exhaust fumes do not smell once the cat is warmed up. I know it isn't the desire of most here but adding the cat had no negative effect on power and in my world of EVs and muted new cars, it is still the loudest thing on the road around here.

mikedsilva · 03-08-2025, 08:44 PM

Does anyone have any video links to decent audio of the above muffler?

mikedsilva · 03-08-2025, 08:47 PM

Quote:

Originally Posted by RarlyL8

How quiet does it need to be?
Our Street mufflers are not what I would consider loud, about twice the dB level of stock. Important part is to retain a straight through pathway as turbos don't like baffling or chambers.

Doesn't need to be stock quiet...

I'm also interested in the type of sound.. not just the db level.

From what I have heard, resonator style mufflers tend to make them sound throbby and dull/woolly.. which is what I currently have.

Not sure on the internal construction of your muffler above?

I have a feeling that mufflers that are chambered tend to produce that raspy style sound.. but like you say, turbos need a free flowing path...

Would be keen to hear some audio of that muffler you pictured.

dedyplay · 03-08-2025, 10:15 PM

They sound awesome.

RarlyL8 · RarlyL8's Garage

Our muffler is straight through using a flame tube that has sound deadening material packed in the case (like a bullet muffler).
Tone is a combination of the headers and muffler. Our headers are tuned, no flat sound like short tube headers. The car in this video has our tuned headers and street muffler. Skip to 2:40 for some fun!

dedyplay · 03-09-2025, 10:17 AM

Nice.

mikedsilva · 03-09-2025, 01:51 PM

Quote:

Originally Posted by RarlyL8

Our muffler is straight through using a flame tube that has sound deadening material packed in the case (like a bullet muffler).
Tone is a combination of the headers and muffler. Our headers are tuned, no flat sound like short tube headers. The car in this video has our tuned headers and street muffler. Skip to 2:40 for some fun!

Brian
THAT SOUNDS AMAZING!!!

mikedsilva · 03-09-2025, 07:52 PM

So in my quest to learn/understand....

At lower rpm, my car has a sound more akin to a Subaru WRX or even a V8 at times... I am running the stock heatexchangers, j Pipe and the short Vibrant Ultra Quiet Resonator. Is that V8 or "throbby" exhaust note more due to the stock header system? At higher rpm, it all smooths out and sounds ok. (yes, I agree chasing a nice exhaust note is rather vain)

And would tuned headers give that smoother, raspier note. That Ruf posted by Brian above, with its street muffler, sounds perfect to me.

RarlyL8 · RarlyL8's Garage

Yes the flat note is a product of unequal length primaries. It gets better at higher RPM but still not close to a true tuned sound. The sound is part of the experience and enjoyment of driving, worthy of consideration. I've replaced several sets of standard short tube headers just for that reason alone.
This 930 in this video has our headers and Zork tube. You can really hear the tuned sound even at low RPM. At high RPM it screams! I still laugh out loud every single time my car hits boost!

mikedsilva · 07-09-2025, 10:35 AM

ok...
so my quest for a quieter muffler continues.
I engaged a shop here to make me a muffler similar to the Magnaflow one at the top of the thread.

Here is a pic.

Maybe it's because he used cheap mufflers but this thing was louder than my single Vibrant Ultra Quiet Resonator.

Here's a video of it.

I'm now thinking to try a 1 in 1 out muffler like

Maybe with a cat converter too?
Only potential issue is these have a 2.5inch diameter inlet/outlet as opposed to 3 inch.. would this be detrimental to flow enough to affect output?

Mtsurfposse · 07-09-2025, 04:00 PM

1” per horsepower NA. If this is your turbo you’ll want more but I’ve never seen what the turbo ratio is it’s just described as “more than NA”. If you have too big pipe you loss some bottom end power

mark houghton · 04:50 PM

An awful lot of science goes into mufflers, headers, and such....and I'm sure a lot of trial and error. Guys like Brian and Fabspeed to name a couple have got the choices dialed in for our 930's.
My limited experience is as this: stock OEM muffler with cat, stock muffler with cat bypass pipe, B&B muffler passenger-side exit, and current Borla. I think I liked the B&B the most as to tone.
I still have the B&B taking up shelf space...need to clean it up and perhaps sell it.

mikedsilva · 07-09-2025, 07:31 PM

Quote:

Originally Posted by Mtsurfposse

1” per horsepower NA. If this is your turbo you’ll want more but I’ve never seen what the turbo ratio is it’s just described as “more than NA”. If you have too big pipe you loss some bottom end power

Are you saying that if I only had a 2.5 inch muffler, I'm capping myself at 250hp?

bpu699 · 10-14-2025, 10:48 AM

Interesting... I didn't know turbocraft made those exhausts... I have that exact exhaust, but with only one muffler cannister on it...

The car sounds a bit "v8-ish." Not bad, but more of a rumble...

Its just too loud in the car for my old ears...

I did install one of those muffler inserts, that effectively drops the diameter from 3 inches to 2 inches and it was MUCH quieter... I was pretty shocked...

But it did choke the motor a bit, and got rid of the turbine whoosh that I love to hear...

Looking into getting one of Brians mufflers soon...

bpu699 · 10-14-2025, 10:50 AM

Quote:

Originally Posted by mikedsilva

Are you saying that if I only had a 2.5 inch muffler, I'm capping myself at 250hp?

There's a video on you tube where guys took a 900 HP turbo v8 and ran it with a 4 inch pipe, 3 inch pipe, and 2 inch pipe...

The TOTAL horsepower lost going from a 4 inch to a 2 inch was 100hp... the motor still churned out 800hp..

But, the motor ran much hotter...

kamaro · 10-15-2025, 12:29 AM

Here is a video of my car, its a 3.4 with GT35 turbo and Magnaflow straight through muffler, the exhaust tailpipe on the passenger side and the wastegate dump on the driver's. That will give an idea about the sound. I can tell you its about %30 louder than a stock 3.3, it has a sharp note when idle but a good sound on boost blasts.

https://www.youtube.com/watch?v=QSmTgc5YM2U

mikedsilva · 10-15-2025, 03:16 AM

Quote:

Originally Posted by kamaro

Here is a video of my car, its a 3.4 with GT35 turbo and Magnaflow straight through muffler, the exhaust tailpipe on the passenger side and the wastegate dump on the driver's. That will give an idea about the sound. I can tell you its about %30 louder than a stock 3.3, it has a sharp note when idle but a good sound on boost blasts.

I ended up having a Magnaflow muffler fitted too. It's a 3 inch oval with offset at one end. I got the 18 inch long one. It only just fits!
Model is 12259

In this photo it is mounted a bit low. I've since had it re mounted and tucked up.
My wastegate just exits toward the ground.
I contemplated getting it routed to the left side exit (the magnaflow exits on the right side) but if I was to have the WG pipe upsized to 3 inch to match the muffler tip wouldnt that act like a megaphone and make it way too loud?

As it is, my engine is fairly quiet. Idle is a nice muted bassy tone. Cruising is nice and quiet. But when the revs are up and you stomp on it, it absolutely screams. Not just the wastegate, but the muffler too.

I really like it. Quiet when you aren't driving like a tool, but the a screamer when you want to be a knob.