This brings up a thought that some of the muffler systems may be subject

to

short life.  I don't know Finn's configuration, but it sounds like the

two

exhaust pipes come out of the engine, directly into a tangential entry

into a

larger piece of tubing. Type "A"

A Type "A" muffler will have a possibility of fatigue-stress cracking at

the

junction of the exhaust header tubes into the muffler, due to repeated
thermal expansion and contraction of the muffler, with the header tubes

being

short and rigidly held. The muffler will expand more than the inter tube
spacing, each time the engine is fired up.
Bill Schertz

Al Gietzen wrote:

With stainless steel you have the further problem of stress corrosion at
these temps weakening the material.  I have a "type A" configuration on my
20B, but using inconel.  Do you suppose it is still a problem?

Al Gietzen

Tracy was pushing his luck with .035 SS.
You could put a slip joint in the muffler if it proves to be a problem
with type A mufflers.

Cheaper than Inconel flex tubing as shown in this Racing Beat Inconel
turbo 3 rotor exhaust manifold. Jim spent about $3,000 on this piece. 

Paul Lamar


 
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