Muffler suggestions

f117rt

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I've got stock duals and looking for some nice sound for the exhaust.

I have Magnaflow catbacks on my G8GT and love the deep low tones.

The problem is that I am not sure if it will sound the same with the Magnaflows with the 351 without all of the cats and resonators.

And hopefully no droning!

Any one with experience using Magnaflows chime in.

Also anyone that can suggest any other mufflers with the sound I am looking for?

 

nosdelacruz

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I have 3 inch magna flow glasspack and all I can say is they sound amazing! I went with cherry bombs and hated them so I swapped to magnaflow. The sound is super low and deep. But, they have some drone issues. If you are worried about drone issues go with the dynomax VT muffler. You won't get the deep tone, but it will sound like a muscle car with no drone issues.

 

caspianwendell

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I guess i'm old but I still love the sound of flowmasters series 40

 

Totalled

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My favorite are "turbo" style muffler. I went with Hooker aerochamber's this time to be different. They sound like the turbos, but deeper... And they don't have the glasspackesk "blat blat" that I don't like about magnaflows, nor the "fart in a garbage can" tinny sound that flowmasters can have.

[video=youtube]

 

MechEng

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Is it normal for a 351C 2V to be super quiet? When I first got mine running I was astonished at how little noise it made. My resonator and muffler are rather well rusted out as well. Is the general thought to go to a dual exhaust set-up and run twin mufflers? Totalled, yours sounds simply amazing, that perfect muscle car gurgle, very nice choice!

 

Blueoval71

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http://www.spintechmufflers.com/

These used to be called Spintrap mufflers, but the original owners of Dr. Gas sold the rights to the guy that was actually building the mufflers for them several years ago. I have been running these since 94 and wouldn't consider using anything else on a muscle car. They are deep and throaty without a lot of droning. At idle they have a good rumble and actually smooth out at higher rpm.

 

cazsper

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1973 Mach-1: 351c 4V, C-6, 3.73:1 gears and a long "To Do" list..
I've heard that an X-pipe helps "mellow" the exhaust sound and usually eliminates the drone. Does anyone know if this is true?

 

Don65Stang

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The question of an x-pipe and reduced drone is very scientific in nature. The same physics for organ pipes come into play. The drone comes from the frequency of the pipe matching the harmonics of the engine frequency. The X-pipe puts a node in the overall length of the pipe and changes the pipe's musical note. The shortened length of pipe raises the frequency at which the harmonic tune begins to resonate. The other part of the equation is that there are naturally occuring notes in the pipes. So the pipe frequency could be a multiple of the base frequency. Like music notes repeating an octave higher or lower. So introducing a forced node via x-pipe may not change the rest or the natural repeating nodes.

An x-pipe may move the rpm at which the drone happens to a higher rpm. There are many factors with pipe diameter and legenth being the two big ones. A best case senario to eliminate drone completely is to introduce nodes at other points in the system so that the laminar frequency flow is disrupted into a shaken up non-repeating pattern; meaning no pattern at all.

 

Jim and Jutta

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I guess i'm old but I still love the sound of flowmasters series 40
+1

 

Mister 4x4

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I have Pypes Street Pros on mine w/2.5" stainless exhaust with an X-pipe behind Hooker ceramic-coated Competition long-tube headers.

I really like the way mine sounds... although I was expecting a little more bass resonance, but I'm good with it.

 

cazsper

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1973 Mach-1: 351c 4V, C-6, 3.73:1 gears and a long "To Do" list..
Don65stang,

That was interesting. Thanks.. When I first bought my '68, it had dual exhaust with resonators where cataletic converters would be on a modern car. I don't see anyone sell resonators these days but could glasspacks (cherry bomb, magnaflow, etc) be used in its place? And would it work?

If so, if you were already running a set of Magnaflow glasspacks and you liked them except for the drone, might another set work as resonators and still not cause much back pressure (if any) because they are a "through" design and not a baffle style? I understand running two glasspacks on each side seems redundant but if it works...

 

Mach1JB

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+1 for the 40 series

 

wwhite72

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Don, i have he factory H pipe design, which i have read produces better scavenging effect on the 351c. Do you have any idea if the x pipe has a different effect than the H pipe on drone? Because i get very little on my dual exaust with standard turbos. I'd like to try magnaflow stainless steel for a more pronounced (brighter) exhaust tone. I done care for flowmaster hollow notes. And i might mention that drone is something even the best car designers cannot always get rid of; i had a 2002 german car that would give you a headache in 5 minutes if i opened the sunroof while driving in town. Was horrible. Made your ears pop and the rear view shudder. But less at 1500k rpm and nothing if you closed the windows. Suked in summer.

 

Don65Stang

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Don65stang,

That was interesting. Thanks.. When I first bought my '68, it had dual exhaust with resonators where cataletic converters would be on a modern car. I don't see anyone sell resonators these days but could glasspacks (cherry bomb, magnaflow, etc) be used in its place? And would it work?

If so, if you were already running a set of Magnaflow glasspacks and you liked them except for the drone, might another set work as resonators and still not cause much back pressure (if any) because they are a "through" design and not a baffle style? I understand running two glasspacks on each side seems redundant but if it works...

Don, i have he factory H pipe design, which i have read produces better scavenging effect on the 351c. Do you have any idea if the x pipe has a different effect than the H pipe on drone? Because i get very little on my dual exaust with standard turbos. I'd like to try magnaflow stainless steel for a more pronounced (brighter) exhaust tone. I done care for flowmaster hollow notes. And i might mention that drone is something even the best car designers cannot always get rid of; i had a 2002 german car that would give you a headache in 5 minutes if i opened the sunroof while driving in town. Was horrible. Made your ears pop and the rear view shudder. But less at 1500k rpm and nothing if you closed the windows. Suked in summer.
Dang! I just did a fantastic write up about this using organ pipes, tubas, piccolo, and their associated frequencies. It was so good I should be awarded the music icon! Lol

But my ineternet browser crashed and shut down when I hit the post button. That sucks! For the moment be thinking about a trumpet and a flute and what happenes to the sound (frequency) when the trumpet valves or flute buttons change the characteristics of those "pipes". I'll try to do a rewrite of my glorious post later. It may be a couple of days but I'll get back to it. I'm driving all day tomorrow returning home. In the meantime you guys can try googling search terms like organ pipes, exhaust, node and drone. I'm sure there will be some good info out there somewhere on the net...just not as good as my lost post. Lol

 

cazsper

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1973 Mach-1: 351c 4V, C-6, 3.73:1 gears and a long "To Do" list..
I found this on line. I thinks basically what Don65stang was saying, just dumbed up a little so I could understand it..lol :

The way I understand it, all mufflers have some degree of resonator behavior in them, by virtue of being a constrained air mass in the body of the muffler with an entrance and exit of distinct diameter. Naturally, the muffler handles more tasks than just being a resonator, but those are the chief aspects that give it a mild resonator behavior. The muffler typically has more elaborate construction inside to achieve its primary tasks (internal baffles, channels, flow-paths, etc).

An actual "resonator" is mostly just a hollow shell with an entrance and exit (or maybe just a perforated, flow-through design) so that it can achieve a singular task of introducing a Hemholtz resonator effect in series or in parallel with the exhaust. Designs may vary across brands, but they generally are not built to fulfill the full application that a muffler does (muffling and high-temp durability of fresh exhaust). The case material is typically a thicker gauge material so as to ensure a stable tuning effect (think of it like a loudspeaker, where you want sturdy, non-flexing walls in the cabinet).

So what does the resonator effect do? It introduces an acoustic notch at a distinct frequency. The tuning of the resonator is important such that the notch frequency coincides right where the drone frequency of the exhaust system is. It cancels out that drone, so that you still get most of the sound of the exhaust system at other frequencies, w/o the drone frequency hammering you over the head when you cross a certain rpm.

Perhaps a chief functional difference between using a glasspack vs. using a resonator, is that the glasspack can serve as a mild resonator with some additional damping in effect by virtue of the glasspack media (hence, making the operation of the notch frequency a bit less pronounced, allowing a more "assertive" exhaust sound with some amount of drone getting through). The resonator is just a resonator with little or no damping. As the vids posted earlier demonstrate, the glasspacks also have their own distinctive sound (whether by the flexing of the glass media or just being a flow-through design that allows higher sound harmonics from the engine pass through, I dunno), with the rhythmic, high-pitched cracking sound.

 

IA Rider

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I have Hooker 2.5" aerochambers with H pipe on my 83 GT and get alot of coments on how nice it sounds. I plan to use aerochambers with H pipe on my 351C mach1 hoping for that same deep sound.

 

Don65Stang

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Exactly Cazsper. The resonator creates a node. Perhaps calling them an anti-resonators would be better. Kind of like calling a fire truck to put out the house fire. A better name would be them anti-firetrucks.

 
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