# Exhaust Extension: Preferred Off-The-Shelf Tubing/Fittings?



## PeteCress (Feb 9, 2014)

Got a couple of Honda Eu2000i's that I want to run inside a garden shed with exhaust vented to the outside - maybe eventually even to a stack on the side of the shed for added noise reduction.

The muffler outlet is about 1 cm in diameter and the room to weld/braze some sort of extension sleeve to the muffler (i.e. the hole in the case around the muffler outlet) is 3 cm. viz: http://tinyurl.com/k9yd2gd

My plan is to weld/braze on extensions about 3" long and have them serve as attachment points for flexible metal tubing. The tubings from each gennie would merge at some point and a single tube would pass through the shed's wall.

Here's the kind of thing I'm talking about:
http://www.simulationfx.com/genny7.jpg
http://tinyurl.com/mr2sndn

For the extensions, I'm thinking relative thin-walled (i.e. not galvanized plumbing pipe) and as close to 3 cm OD as possible to minimize any back pressure.

Word I get is that the muffler's temp does not get over about 250 degrees F.

I am finding quite a bit of that sort of thing, but nobody gets specific about the type/size tubing. One guy did it with flexible gas tubing: http://tinyurl.com/m9c6l6u But the connection to the muffler seems unclear/dicey and I wonder about back pressure from such narrow tubing - especially with a bend or two in it.


*The Question:*

What sort of solid (for the extensions) and flexible tubing am I looking for?

Am I looking in the plumbing world? Electrical? Hot-rod?.... ???


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