Jerry Hey wrote:

 >Paul,  I found this on an internet search under  "flexible exhaust."
 >Would it be of use in our installations?   Jerry

Good work Jerry. I think Mazda uses this stuff. Don't know how it would
hold up in our applications but it is worth a try.

Paul Lamar

I have checked further.   The flexible unit is 100 percent 304
stainless.  It is shipped with ss braiding on the outside but the
part were are interested in is the SS Bellows that is inside.  In
some pictures the unit is shown with end caps.  These are aluminized
steel and we don't want them.   The SS bellows is expanded on each
end so that it will slip over our two inch exhaust pipes   where it
can be welded in line.   It can be purchased without the end caps.
It comes in four, six and eight inch lengths .  Apparently it is OEM
equipment a lot of front wheel drive  vehicles where there is great
relative movement between the softly supported engines and solid
mounted exhaust components. The manufacturer is SENIOR FLEXONICS,
Bartlett, Ill.    Tel: 630-837-1811.   I mentioned that it was for an
"off road vehicle" and got excellent cooperation.    They do not sell
direct.   They have a dealer Marwell Products who faxed  the flyer I
posted.     I don't have their phone number with me but I can post
later it if anyone wants it.

I am thinking of cutting my muffler free and installing the flex
tubes.  That would  give me a chance  to move the muffler down and
away from the side of the engine and maybe even find a way to snake
the exhaust pipes  around to a tuned length.  Don't know if  that is
really possible but I can dream.

As the exhaust gas  moves away from the exhaust port, it must be
cooling.   Is this significant enough to utilize in our designs.
For example,  if the muffler is  twenty inches downstream instead of
two inches,  is it a lot cooler or just barely cooler?         Jerry

This sounds like a job for someone flying that's experimenting with the
exhaust system.. 8-)  With a section of pipe that you were planning on
changing and a few egt probes spaced at 6-12 inches and a rotary switch we
would know the answer.

Speculation mode ON-   Looking at it from the gas flow path expansion, it
may still be burning a few inches from the port.  Also as it runs down the
pipe the pressure wave stretches out lowering the density and thus the
temperature according to the gas law PV=nRT.  That is, it SHOULD be cooler
but that's theory not empirical evidence!

Anyone got a hand full of egt probes you can send to Tracy ...  ;-)

Mike McGee, RV-4 N996RV, O320-E2G, Hillsboro, OR
13B in gestation mode

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