adding stock/small muffler to Skyhawk expansion chamber?

[Fabian]

I'm glad your tensioner has worked for the last 3 years - given the design, i must be doing something completely wrong with my tensioners.

 

[LaLongueCarabine]

Has anyone got the expansion chamber that is shaped like a long diamond with a small can muffler on the end? I can't remember where I saw ít,but it seems like a good design.