wrote:


And since those Aeronca muffs tend to leak a lot, forcing air into
them might cool the pipe too much just when the heat is needed. The OP
needs to seal up those muffs. The connection to the baffling needs to
stay, since a muffed pipe with no airflow (except when carb heat is
on) will overheat and burn out. Piper had plenty of that sort of
trouble on their Cherokees.

The OP gets a 50 RPM drop in cruise, with carb heat. That ain't
much.

Dan

Actually, my muffs fit fairly "airtight" around the exhaust pipes. I
actually had to cut and trim a bit to make them fit at all, so I think
the majority of the heat produced is captured inside the muff. However,
I just don't think the two halves of aluminum have enough thermal mass
to provide a ton of heat to the carb, so I think I still need to come up
with a safe way to add mass inside the muff.

Scott