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[GMCnet] NO muffler [message #81364] Wed, 21 April 2010 18:38 Go to next message
Terry Skinner is currently offline  Terry Skinner   United States
Messages: 379
Registered: January 2004
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Senior Member
Friend called last week from Denver. Was going to replace both
mufflers and I talked him into just leaving them off all together. He
did and replaced them with straight pipes. He loves the sound and more
power. I did the same on a 23 I have here. I couldn't detect any more
noise than before. Just an experiment..........Terry
PS His power loss was from blocked mufflers.
--
Terry Skinner
253-686-2624
Roy. Washington
'76 GMC
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Re: [GMCnet] NO muffler [message #81365 is a reply to message #81364] Wed, 21 April 2010 18:40 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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good to hear

that is what I am going to try on my 23. I live remote, so on the road
again" it should not matter.

thanks
gene


On Wed, Apr 21, 2010 at 4:38 PM, Terry Skinner <gmcnut@gmail.com> wrote:

> Friend called last week from Denver. Was going to replace both
> mufflers and I talked him into just leaving them off all together. He
> did and replaced them with straight pipes. He loves the sound and more
> power. I did the same on a 23 I have here. I couldn't detect any more
> noise than before. Just an experiment..........Terry
> PS His power loss was from blocked mufflers.
> --
> Terry Skinner
> 253-686-2624
> Roy. Washington
> '76 GMC
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
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Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] NO muffler [message #81374 is a reply to message #81364] Wed, 21 April 2010 20:04 Go to previous messageGo to next message
GMC_LES is currently offline  GMC_LES   United States
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Location: Montreal
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Terry,

Have you asked bystanders what thecoach sounds like without Mufflers? The
noise out the tailpipe must be a fair bit louder, but it would be hardly
noticeable from the driver's seat.

I've heard a few coaches with free flowing mufflers and I find them to be
noisy when standing beside them as they pull away. I would imagine no
mufflers would be somewhat louder.


Thanks,
Les Burt

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Les Burt Montreal 1975 Eleganza 26ft A work in Progress
Re: [GMCnet] NO muffler [message #81378 is a reply to message #81365] Wed, 21 April 2010 20:36 Go to previous messageGo to next message
Mike O'Connell is currently offline  Mike O'Connell   United States
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Registered: November 2008
Location: Deerfield MA
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Member
The PO of my coach bolted on a set of "cherry bomb" straight thru glass packs in place of the front mufflers. Quite a noise I got going on there. I originally thought I had a hole in a pipe somewhere.

Mike O'Connell Deerfield, MA '75 Eleganza
Re: [GMCnet] NO muffler [message #81382 is a reply to message #81378] Wed, 21 April 2010 20:55 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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I can tell you what a big caddy with twin turbos sounds like when it blows by at 75-80 mph. Scared me so bad I nearly left the road. Can you say Jet Engine?
The driver looked kinda like the men I used to hear about in those kamakazi planes.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] NO muffler [message #81383 is a reply to message #81382] Wed, 21 April 2010 20:57 Go to previous messageGo to next message
Harry is currently offline  Harry   Canada
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Did he have a little leather helmet and goggles?
I think I met him in Fremont.
Re: [GMCnet] NO muffler [message #81384 is a reply to message #81382] Wed, 21 April 2010 20:58 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
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Senior Member
Them Thar Mitsubishi Zero Jobs, eh?


WD0AFQ wrote on Wed, 21 April 2010 18:55

I can tell you what a big caddy with twin turbos sounds like when it blows by at 75-80 mph. Scared me so bad I nearly left the road. Can you say Jet Engine?
The driver looked kinda like the men I used to hear about in those kamakazi planes.
Dan



-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
Re: [GMCnet] NO muffler [message #81388 is a reply to message #81364] Wed, 21 April 2010 21:07 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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PSSTTT..... He's one of us.... he's on our side...

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] NO muffler [message #81390 is a reply to message #81374] Wed, 21 April 2010 21:16 Go to previous messageGo to next message
Terry Skinner is currently offline  Terry Skinner   United States
Messages: 379
Registered: January 2004
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Senior Member
Randy Burns put a muffler in the rear and a "Y" up front. Dealer said
it was a replacement for a Mustang. I thought it sounded pretty good.
A little resonant like the ol' cherry bombs but his wife didn't like
the sound. What can I say..........Terry
PS Maybe that is why they are glad to see me go.<VBG>

On Wed, Apr 21, 2010 at 6:04 PM, Les Burt <burtco99@yahoo.com> wrote:
> Terry,
>
> Have you asked bystanders what thecoach sounds like without Mufflers? The
> noise out the tailpipe must be a fair bit louder, but it would be hardly
> noticeable from the driver's seat.
>
> I've heard a few coaches with free flowing mufflers and I find them to be
> noisy when standing beside them as they pull away. I would imagine no
> mufflers would be somewhat louder.
>
>
> Thanks,
> Les Burt
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Terry Skinner
253-686-2624
Roy. Washington
'76 GMC
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Re: [GMCnet] NO muffler [message #81396 is a reply to message #81382] Wed, 21 April 2010 21:36 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Dan,
Was his eyes squinted and buck teeth showing with a grin?
If Grace found out that I was not running a muffler at all she will
insist that we put on on..

The 23' coaches might be different as the length of the pipe can be at
a point on the sound wave where it will be minimum noise. I forgot the
Sine wave stuff from college.
On my 4" pipe I can move the length of the pipe to control sound for
different RPM.




On Wed, Apr 21, 2010 at 6:55 PM, Dan Gregg <gregg_dan@hotmail.com> wrote:
>
>
> I can tell you what a big caddy with twin turbos sounds like when it blows by at 75-80 mph. Scared me so bad I nearly left the road. Can you say Jet Engine?
> The driver looked kinda like the men I used to hear about in those kamakazi planes.
> Dan
> --
> Dan & Teri Gregg
>
> danandteri.blogspot.com
>
>
>
> ///Halon Automatic Fire Extinguishers
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Jim Kanomata
Applied/GMC, Fremont,CA
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Jim Kanomata
Applied/GMC
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www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] NO muffler [message #81403 is a reply to message #81364] Wed, 21 April 2010 23:09 Go to previous messageGo to next message
jknezek is currently offline  jknezek   United States
Messages: 1057
Registered: December 2007
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Senior Member
My coach just got fitted with flow through mufflers and I can say the sound makes a big difference. My wife was at the curb the first time I took off and she thought an airplane was about to land on her. Once you get up a few rpms though, the noise dies down pretty well. In the coach it isn't a big deal at all but I wouldn't want to be rocking a baby to sleep at a stop light when I take off. Still, the pickup in power from headers, bigger pipes, and the flow throughs is pretty amazing...

Thanks,
Jeremy Knezek
1976 Glenbrook
Birmingham, AL
Re: [GMCnet] NO muffler [message #81427 is a reply to message #81364] Thu, 22 April 2010 07:40 Go to previous messageGo to next message
Larry C   United States
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
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Senior Member
I talked him into just leaving them off all together. He
did and replaced them with straight pipes. He loves the sound and more power. I did the same on a 23 I have here. I couldn't detect any more noise than before. Just an experiment..........Terry
________________________________________________________


In a past conversation, there was talk with the ONAN exhaust going up a tube in the rear of the GMC. the ONAN exhaust pipe when to a venturi like point, where the vertical tube went up. It was said the sound was minimal or none.

If this works this way, would this also cut sound from the engine exhaust as well?

I ask because I have not done the ONAN version yet.

I have read an article about a auto manufacturer experimenting with no mufflers, just an inverse sound to cancel the exhaust sound. What these engineers come up with....


LarC ( Always improving, Always one step better. )



Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" /> http://www.gmceast.com/travel
_
Re: [GMCnet] NO muffler [message #81436 is a reply to message #81383] Thu, 22 April 2010 09:09 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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No, but in true Kamakazi fashion, he had on a parachute.

On Wed, Apr 21, 2010 at 6:57 PM, David H. Jarvis <jarvis210@shaw.ca> wrote:
>
>
> Did he have a little leather helmet and goggles?
> I think I met him in Fremont.
> --
> "I've always been crazy, but it kept me from going insane"
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--
Steve Ferguson
'76 EII
Sierra Vista, AZ
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Re: [GMCnet] NO muffler [message #81448 is a reply to message #81427] Thu, 22 April 2010 10:04 Go to previous messageGo to next message
Terry Skinner is currently offline  Terry Skinner   United States
Messages: 379
Registered: January 2004
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Senior Member
Back in my motorcycle days we "rolled our own." We rolled cones out of
20 gauge sheet metal, then gas welded them right at the track to make
expansion chambers. Don't know that I learned all that much but the
one thing I did learn was that the temperature of the exhaust gas
would effect the speed of sound. Back to GMC, how about spraying water
into the exhaust pipe to change the temperature of the gasses thus
effecting the speed of sound and deadening the noise?? Where do we get
all this water?? There is a black tank back there full of old used
water. Just a thought...............Terry

On Thu, Apr 22, 2010 at 5:40 AM, Larry <slawrence111@yahoo.com> wrote:
>
>
>  I talked him into just leaving them off all together. He
> did and replaced them with straight pipes. He loves the sound and more power. I did the same on a 23 I have here. I couldn't detect any more noise than before. Just an experiment..........Terry
> ________________________________________________________
>
>
> In a past conversation, there was talk with the ONAN exhaust going up a tube in the rear of the GMC.  the ONAN exhaust pipe when to a venturi like point, where the vertical tube went up.  It was said the sound was minimal or none.
>
> If this works this way, would this also cut sound from the engine exhaust as well?
>
> I ask because I have not done the ONAN version yet.
>
> I have read an article about a auto manufacturer experimenting with no mufflers, just an inverse sound to cancel the exhaust sound.  What these engineers come up with....
>
>
> LarC ( Always improving, Always one step better. )
>
>
> --
> Gatsbys' CRUISER :d
> 74 GLACIER X, 260
> 455/APC/4 bagg'r(ver3)
> Remflex Manifold gaskets
> _______________________________________________
> Purchased 08-18-04
>
> _
>
>
>
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>



--
Terry Skinner
253-686-2624
Roy. Washington
'76 GMC
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Re: [GMCnet] NO muffler [message #81449 is a reply to message #81365] Thu, 22 April 2010 10:17 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
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Senior Member
This is an interesting thread....... I'm in need of a new exhaust system........so what is the configuration of the exhaust system with no mufflers??

Can you run the pipes from the engine into a Y, then to the rear of the coach and skip the muffler ??

I'm having a hard time believing that it wouldn't be obnoxiously loud.

Oh, just curious, what is the Flowmaster Part Number for the muffler at the rear on a single muffler 3" system ???

Have a great day !!!
Ray


Ray & Lisa Erspamer
78 Royale Center Kitchen
TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: Mr.erf ERFisher <mr.erfisher@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Wed, April 21, 2010 6:40:35 PM
Subject: Re: [GMCnet] NO muffler

good to hear

that is what I am going to try on my 23. I live remote, so on the road
again" it should not matter.

thanks
gene


On Wed, Apr 21, 2010 at 4:38 PM, Terry Skinner <gmcnut@gmail.com> wrote:

> Friend called last week from Denver. Was going to replace both
> mufflers and I talked him into just leaving them off all together. He
> did and replaced them with straight pipes. He loves the sound and more
> power. I did the same on a 23 I have here. I couldn't detect any more
> noise than before. Just an experiment..........Terry
> PS His power loss was from blocked mufflers.
> --
> Terry Skinner
> 253-686-2624
> Roy. Washington
> '76 GMC
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] NO muffler [message #81459 is a reply to message #81364] Thu, 22 April 2010 11:49 Go to previous messageGo to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
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Registered: May 2009
Location: Los angeles
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Senior Member

I was thinking about redoing my exhaust with dual side pipes. would take getting creative with the routing of the the exhaust but should be possible. the GF wanted something similar to diesel stacks which I thought about and it would look cool, but would add drag and something hanging on the sides to snag on sign posts and the like....


I am interested in hearing more about the Onan "Silencer" modification....


73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
Re: [GMCnet] NO muffler [message #81460 is a reply to message #81459] Thu, 22 April 2010 11:58 Go to previous messageGo to next message
fred v is currently offline  fred v   United States
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Duce Apocalypse wrote on Thu, 22 April 2010 11:49

I was thinking about redoing my exhaust with dual side pipes. would take getting creative with the routing of the the exhaust but should be possible.

that used to be an available after market item. i've seen a coach the had them. we used to call them "lakes pipes".


Fred V
'77 Royale RB 455
P'cola, Fl
Re: [GMCnet] NO muffler [message #81463 is a reply to message #81460] Thu, 22 April 2010 12:28 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
Senior Member
Speedway motors sells something called an auger muffler insert.
It looks just like a bug drill bit, has a 1" center tube with disks placed every 2 inches or so. the disks are bent to kindof make a spiral.

I use 2 per side on the Vette

I use them on my Vette in the side pipes ( on Vettes they are side pipes, on street rods they are lake pipes) they work pretty good and don't rob too much horsepower..

I'd imagine on the GMC, with less airflow and lower compression they'd work really well.

Best of all they are cheap and can fit inside a 3" pipe!

http://www.speedwaymotors.com/Speedway-Auger-Style-Muffler,1736.html


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] NO muffler [message #81469 is a reply to message #81459] Thu, 22 April 2010 12:55 Go to previous messageGo to next message
Bob Raef is currently offline  Bob Raef   United States
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Location: Lubbock, TX
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Senior Member
Camping World has the Onan exhaust pipe in its catalog. They call it a Gen-turi.

Bob Raef, KF5TYA
(575) 973-2273
Re: [GMCnet] NO muffler [message #81476 is a reply to message #81449] Thu, 22 April 2010 14:22 Go to previous messageGo to previous message
Terry Skinner is currently offline  Terry Skinner   United States
Messages: 379
Registered: January 2004
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Senior Member
If you are going to install one muffler anyway why not go ahead and
put straight pipes on. You can go back and install the muffler any
time you want, any way you want.

On my 26 the pipes run from the headers into a 2.5" Y, then into a 3"
pipe that runs down the right side, then into a muffler and out the
back. The 23 with no mufflers, the 26 with one muffler in the back,
and the 26 that has two mufflers in the stock configuration are all
sitting here in a row. You are welcome to some on over and we will
start them all up and you can listen to them. Just trying to
help.<G>...........Terry

On Thu, Apr 22, 2010 at 8:17 AM, Ray Erspamer <78gmc-royale@att.net> wrote:
> This is an interesting thread....... I'm in need of a new exhaust system........so what is the configuration of the exhaust system with no mufflers??
>
> Can you run the pipes from the engine into a Y, then to the rear of the coach and skip the muffler ??
>
> I'm having a hard time believing that it wouldn't be obnoxiously loud.
>
> Oh, just curious, what is the Flowmaster Part Number for the muffler at the rear on a single muffler 3" system ???
>
>  Have a great day !!!
> Ray
>
>
> Ray & Lisa Erspamer
> 78 Royale Center Kitchen
> TZE368V101144
> Wauwatosa, Wisconsin 53226
> Email: 78GMC-Royale@att.net
> 414-745-3188
> Web Site: http://ray-lisa.page.tl/
>
>
>
>
> ________________________________
> From: Mr.erf ERFisher <mr.erfisher@gmail.com>
> To: gmclist@temp.gmcnet.org
> Sent: Wed, April 21, 2010 6:40:35 PM
> Subject: Re: [GMCnet] NO muffler
>
> good to hear
>
> that is what I am going to try on my 23.   I live remote, so on the road
> again"  it should not matter.
>
> thanks
> gene
>
>
> On Wed, Apr 21, 2010 at 4:38 PM, Terry Skinner <gmcnut@gmail.com> wrote:
>
>> Friend called last week from Denver. Was going to replace both
>> mufflers and I talked him into just leaving them off all together. He
>> did and replaced them with straight pipes. He loves the sound and more
>> power. I did the same on a 23 I have here. I couldn't detect any more
>> noise than before. Just an experiment..........Terry
>> PS His power loss was from blocked mufflers.
>> --
>> Terry Skinner
>> 253-686-2624
>> Roy. Washington
>> '76 GMC
>> _______________________________________________
>> GMCnet mailing list
>> List Information and Subscription Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> Gene Fisher -- 74-23,77PB/ore/ca
> “Give a man a fish; you have fed him for today --- give him a URL and
> -------
> http://gmcmotorhome.info/
> Alternator Protection Cable
> http://gmcmotorhome.info/APC.html
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
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> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Terry Skinner
253-686-2624
Roy. Washington
'76 GMC
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