Quieter Exhaust addon's....

Thanks wallaka. Yeah it seems that the names are used interchangeably, and after originally posting this question and some more ‘exhaustive’ research :roll: :roll: :roll: , here is some additional food for thought and what I’m now thinking.

I’m wondering if it’s not one of those old geometry type axioms…all glass packs, mufflers, and other sound altering chambers are resonators, but not all resonators are glass packs. From what I’ve been able to find, it appears that some resonators (perhaps these are referred to as true ‘Helmholtz Resonators’…not sure) do not have any packing (ie fiberglass, glass wool or some such).
It also seems to be a general conclusion that the packing material inside glass pack (resonators) breaks down over time and they get louder vs a resonator with no packing.
Of course this is all info gleamed from many internet searches so how much of that can you believe

I ended up opting to experiment with a cheap Jones Exhaust Resonator from Summit in my case. According to Jones Comp, it doesn’t have any packing in it, and has louvered openings to modify sound (instead of perforations). I’ll post my results under one of the multiple 2” exhaust threads already started, but here’s the best comparison pic of these two styles I could find…
http://www.roadraceengineering.com/part ... uvered.jpg

Here is Waldron’s explanation of resonators…
http://waldronexhaust.com/basics.htm
“Resonators

Resonators are utilized on a wide variety of passenger car and truck exhaust systems. They typically utilize a “straight-through” case or tube that attenuates and tunes the sound of the exhaust pulses. Resonators are most often installed just before exit point of the exhaust system, but in some applications the resonator is installed in front of the muffler. Some resonators are designed as simple, hollow expansion or sound chambers with no sound absorbing materials. These are acoustically tuned to deliver the desired exhaust note. They primarily use reflective wave cancellation techniques to eliminate the undesired frequencies while allowing desired frequencies to pass unabated.

Most exhaust system providers will provide replacement exhaust systems with or without the resonator component. A straight pipe replacement can be installed if the resonator is not desired. Without the resonator, your exhaust system will usually sound slightly louder and less mellow, with a sharper and “raspier” exhaust note evident under hard acceleration.”

AFAIK Scott Fuller also developed a reproduction of the old 289 Hipo (Arvinode) exhaust system that was covered in Mustang Monthly.
http://www.mustangmonthly.com/techartic ... index.html

Still couldn’t find definitive reasons for putting one fore or aft of the muffler, but my guess is that in the case of the former it would not only have a greater silencing effect but also a greater flow restriction

I'll edit back a link to the sound takes and experimenting with the Jones Resonator when I get them posted.

EDIT: here they are...may not help you much with your plans MPG being a boring old stocker , but maybe it will
Straight pipe after muffler
Resonator with flow
Resonator into/against flow
Final with 2 to 2.25 ss tip

Louvered mufflers are the single worst thing you can add to your car to disrupt flow in your exhaust system. If you want to go with them, I'd size up by a full half inch to minimize it.

And yeah, old-school glass packs break down. Though there are some with heat-resistant or heatproof packing. Might look into Magnaflow, I've heard good things about their stainless stuff and had one added to my M3. It made the high-pitched 'rasp' that plagues those cars go away, while leaving the low rumble there.

There's an article on exhaust system theory on Popular Hot Rodding's site written by David Vizard; it's pretty eye-opening stuff.

found it! http://www.popularhotrodding.com/engine ... index.html

this is alot of reading, i'll have to pruse through it more.

i'll be grabing some cheap resonators and throw them before the mufflers, at lease it'll be a striaght though. but I deffeintly will miss the raspy sound.

will post sound clip after i'm done.

Richard

Yeah, thanks wallaka lot's of info to get my tiny brain around...but especially liked the part on 'scavenging' and the 5th cycle

@MPG I edited my links from my resonator experiment above...no thread hi-jack intended.
BTW I like the sound of your setup 8) but can also relate on the noise level issues.
Good luck!

wallaka":31wzaa7w said:

Louvered mufflers are the single worst thing you can add to your car to disrupt flow in your exhaust system. If you want to go with them, I'd size up by a full half inch to minimize it.

And yeah, old-school glass packs break down. Though there are some with heat-resistant or heatproof packing. Might look into Magnaflow, I've heard good things about their stainless stuff and had one added to my M3. It made the high-pitched 'rasp' that plagues those cars go away, while leaving the low rumble there.

There's an article on exhaust system theory on Popular Hot Rodding's site written by David Vizard; it's pretty eye-opening stuff.

found it! http://www.popularhotrodding.com/engine ... index.html

Click to expand...

wow man
i'm about five paragraphs into that and my brain is melting

Given these numbers you can see the exhaust system draws on the intake port as much as 500 percent harder than the piston going down the bore. The only conclusion we can draw from this is that the exhaust is the principal means of induction, not the piston moving down the bore.
and this is where my brain 'sploded all over everything
man

A few of us have the 264/274 cam, and I'm sure we'd like to know how to best optimize our systems.
So I'll be following this thread, but have very little to offer. : :arrow:

Asa":1tc02556 said:

wallaka":1tc02556 said:

Louvered mufflers are the single worst thing you can add to your car to disrupt flow in your exhaust system. If you want to go with them, I'd size up by a full half inch to minimize it.

And yeah, old-school glass packs break down. Though there are some with heat-resistant or heatproof packing. Might look into Magnaflow, I've heard good things about their stainless stuff and had one added to my M3. It made the high-pitched 'rasp' that plagues those cars go away, while leaving the low rumble there.

There's an article on exhaust system theory on Popular Hot Rodding's site written by David Vizard; it's pretty eye-opening stuff.

found it! http://www.popularhotrodding.com/engine ... index.html

Click to expand...

wow man
i'm about five paragraphs into that and my brain is melting

Given these numbers you can see the exhaust system draws on the intake port as much as 500 percent harder than the piston going down the bore. The only conclusion we can draw from this is that the exhaust is the principal means of induction, not the piston moving down the bore.
and this is where my brain 'sploded all over everything
man

Click to expand...

Yeah my brain does that every time I read one of his articles. Dude is a genius.

I think I've read that article 30 times and still don't quite understand it all.