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Exhaust size? [message #281013] Mon, 29 June 2015 16:28 Go to next message
bpimm is currently offline  bpimm   United States
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My coach has a dual 2 1/4" exhaust on it, the pipe that goes down the driver/left side seems to be in the way of everything I want to work on. how much breathing would I loose if I tied the left side back into the right side? eventually I want to put the stainless system offered by Applied, but for now am I going to hurt the performance?

Thanks


Brian & RaeDean 1973 26' #383 Washougal WA
Re: [GMCnet] Exhaust size? [message #281014 is a reply to message #281013] Mon, 29 June 2015 16:31 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Brian,

Photos of your exhaust system would be helpful.

If you are not signed up on the Photo Site just send them to me: (robmueller at iinet dot net dot au) and I'll post them there for
you.

Regards,
Rob M.
The Pedantic Mechanic

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Brian Pimm
Sent: Tuesday, June 30, 2015 7:28 AM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Exhaust size?

My coach has a dual 2 1/4" exhaust on it, the pipe that goes down the driver/left side seems to be in the way of everything I want
to work on. how
much breathing would I loose if I tied the left side back into the right side? eventually I want to put the stainless system offered
by Applied, but
for now am I going to hurt the performance?

Thanks
--
Brian & RaeDean

1973 26' #383

Washougal WA
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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: Exhaust size? [message #281016 is a reply to message #281013] Mon, 29 June 2015 17:16 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
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bpimm wrote on Mon, 29 June 2015 16:28
My coach has a dual 2 1/4" exhaust on it, the pipe that goes down the driver/left side seems to be in the way of everything I want to work on. how much breathing would I loose if I tied the left side back into the right side? eventually I want to put the stainless system offered by Applied, but for now am I going to hurt the performance?

Thanks


The Applied system merges into one pipe in front of the fuel tanks and runs down the passenger side, as does the stock system. The fuel supply pipe runs down the driver side on mine, not sure there is room for much else.


76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.
Re: Exhaust size? [message #281021 is a reply to message #281016] Mon, 29 June 2015 17:49 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Joe Weir wrote on Mon, 29 June 2015 15:16

The Applied system merges into one pipe in front of the fuel tanks and runs down the passenger side, as does the stock system. The fuel supply pipe runs down the driver side on mine, not sure there is room for much else.


Now add the driver side 2.5" exhaust into that driver side mix, makes it a PITA. I want to take it back to more like the stock system. What size was the stock pipe?


Brian & RaeDean 1973 26' #383 Washougal WA
Re: Exhaust size? [message #281026 is a reply to message #281021] Mon, 29 June 2015 18:07 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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bpimm wrote on Mon, 29 June 2015 17:49
Joe Weir wrote on Mon, 29 June 2015 15:16

The Applied system merges into one pipe in front of the fuel tanks and runs down the passenger side, as does the stock system. The fuel supply pipe runs down the driver side on mine, not sure there is room for much else.


Now add the driver side 2.5" exhaust into that driver side mix, makes it a PITA. I want to take it back to more like the stock system. What size was the stock pipe?


The stock system was 2 1/4 inch down pipes into mufflers. Exit 2 1/4 from the mufflers into a y pipe that was 2 1/2 then the long pipe and exhaust were the same 2 1/2 inch.

Dennis


Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: Exhaust size? [message #281033 is a reply to message #281026] Mon, 29 June 2015 18:56 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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Dennis S wrote on Mon, 29 June 2015 16:07
bpimm wrote on Mon, 29 June 2015 17:49
Joe Weir wrote on Mon, 29 June 2015 15:16

The Applied system merges into one pipe in front of the fuel tanks and runs down the passenger side, as does the stock system. The fuel supply pipe runs down the driver side on mine, not sure there is room for much else.


Now add the driver side 2.5" exhaust into that driver side mix, makes it a PITA. I want to take it back to more like the stock system. What size was the stock pipe?


The stock system was 2 1/4 inch down pipes into mufflers. Exit 2 1/4 from the mufflers into a y pipe that was 2 1/2 then the long pipe and exhaust were the same 2 1/2 inch.


Dennis



It is as Dennis says above. I would seriously that a 2-1/4" system all the way out the back will significantly affect the performance at the RPMs we operate at. That said, I have the two muffler 3" system from Jim K on my coach.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: Exhaust size? [message #281037 is a reply to message #281033] Mon, 29 June 2015 19:41 Go to previous message
George B. is currently offline  George B.   United States
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Just for the fun of it you can see part of my exhaust system on this youtube https://www.youtube.com/watch?v=Ad8hPnRncuE

My system had headers running into two flowmaster mufflers that went to a Y and into a 3 inch exhaust down the passenger side to the rear. The new system has the single spintech muffler with two 2 1/2 (maybe 2 1/4) inch inlets and one three inch outlet running into the existing 3 inch exhaust pipe to the rear on the passenger side. My performance with this setup seems excellent so far. I can say that the 1973,and heavy, 26 foot coach outperforms my 1976 23 foot with stock exhaust by a huge margin. (although the 73 also has a 3.42 drive where the 76 is stock).


George Butts Las Vegas Nevada 73 "Custom 26' Q" & 76 23' Birchaven 71 Honda 600 Coupe & 01 Tracker Toads
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