Has anyone done a study of the internals of high-end mufflers?

You will have a hard time seeing any insides, because in fact most are quite restrictive in nature so that the "pitch" sound can be produced.

Since sound and external finish are more important than function and seem to sell the present aftermarket exhausts, the current makers will continue down this road.

You'll need to cut one open yourself, and when you see the internals you'll wonder how any exhaust gases pass through them!

 

Not a study per say, but a one time experiment......FWIW.......we just cut open the OEM Porsche 911 turbo muffler on a 1992 car........there are only a couple of manufacturer's that even make a system for this car, and they are all pricey due to the low volume......our client just wanted a better sound, since it is darn near impossible to improve HP wise on the OEM Porsche exhaust systems.

What we found inside was a 2" U shaped pipe drilled with numerous holes, underneath a very thick and heavy cladding that looked like steel wool/fiberglass. We removed all the insulation from the muffler, left the pipe in place and welded it back to gether.

The sound improvement was dramatic and quite incredible, the performance the same, and the cost <$100............

 

Most OEM mufflers are designed to silence "noise" to meet federal and state guidelines. They don't particularly care about sound.

Can you imagine a OEM providing a muffler that drones like a TUBI!

Reducing internal restrictions while silencing the exhaust pulses is an art.

Few know the art!

 

I don’t think you will find manufactures willing to show the internals of the system. A lot of design and engineering work goes into them, it would make it very easy for others to copy.

 

I want to contribute something to this thread...so here it goes.....

WHAT'S IT MATTER....in a trend that we're seeing as more and more common, it seems typical that mufflers are being designed to have bypass valves that open to entirely bypass the muffler altogether!

The CS, sport 360, stock 430, Capristo Twin, Kreisseng...all have bypass valves that open to allow the exhaust coming from the cats to just go around the muffler and blast out the pipes without ever seeing any baffling or internals of a muffler. So it stands the reason the muffler of the future is no muffler at all. Too bad this isn't the future of woman's bathing suits!

I've come to understand that other top-end exhaust companies are following suit and plan to also produce their own version of these "bypass the muffler altogether" systems. Ferrari liked it enough to make it their stock OEM system in the 430 and probably the model to follow.

Fascinating question though....

 

I don't agree with this. There is no particular design magic that one could not see by opening a competitor's unit!

I never designed or sold a free flow exhaust system w/o an actual full cutaway to show the entire innerds of the unit.

I was proud to display all my designs.

Plenty tried to emulate my designs, but they got no where trying!

 

Mike,

Your single, 20-something and have a 6' blonde model waiting for you somewhere....shouldn't you be bangin' away on that instead of wondering what's stuffed into the inside of a muffler? You're chasing the wrong muff my friend! (I saw you edited your post...wonder what evil that was?)

As for your question...bypass valves are just butterfly-style disc inside a pipe....when the valve opens it just lets the exhaust flow through. They can be set-up in different ways. In the systems I mentioned above, they are set-up to open and allow the exhaust to go right out the pipes and never go into the muffler. When closed, the exhaust can't get past the valve and instead flows up into the muffler and then out the other pipes. Complicated to write about, simple to see in a picture.

Dude...it's 9:15pm on Saturday night....you have a blood-alcohol level of 0.0 Do something about it...

 

BWAAAAHAHAHAHAHAHAHAHAHAHAHAHAHAAAAA
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Now your shredded-wheat Mike....behold, his divine gloriness reveals himself: 19,000 posts!!!!!!!

 

I didn't think it was that funny......

 

Long time reader of this post. First time posting to an interesting thread. May you point me to several of your cut-away designs Greg?

I'm a transportation design student and would like to spear my design with sound being principal as oppose to form.

Thanks for starting the thread Mike.

Vizal