Not necessarily Russell. If all three outlets are tied

together with a racing beat type exhaust flange it might almost
track the expansion of the muffler.<<<

Marc Wiese wrote:

I think I saw in Bells book or maybe McInnes that the bolt holes should
be enlarged or split to allow the flange to move against the engine and
that each pipe be allowed to float. If it is tight to the engine the
pipes will move and the engine won't. Am I mixed up here?

The bolt holes are split at the outside.  Obviously in my case the pipes are
not allowed to float.   The coefficient of thermal expansion for inconel is
about 11 x 10 to -6 in/in/degree C.  The max temp change from ambient will
be 1600F, or 890 C.  The two outside pipes are about 6 in. from the center
one, so they will want to move about .050 - .060 in..  If the flange expands
about half that, than the differential movement between the muffler and the
flange will be about .025 - .030 in.  Let's see.. what does that tell us?

Anybody want to do some finite element stress analysis?  And at these
temperatures you'd have to factor in "creep".

Al

 
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