I do not know if this muffler was on the Piper that went down with a plugged outlet.

 

There appears to be an inner pipe with flanged tubes and holes from each port. This has a slip joint between the ports. Then an outter cooling sleeve. The flanged tubes with blind flat end caps and many holes were doomed. (In my opinion)

 

Lynn E. Hanover

 

I think the pictures are from Paul Lamar's news group.