I may not be understanding what the 2 rotor version (cool pipe going all
the way through) is supposed to accomplish or maybe my gut-feel thermodynamic
instincts are way off. I can't imagine this would have any significant
effect on exhaust temps, muffler wall temp or sound.
Tracy (been wrong more than once)
Bill,
from the picture you sent, it isn't clear to me where the 'cool tube' ends
inside the muffler. Give me a clue!
Tracy, On the small muffler (2 rotor) the cool tube goes all the way
thru. The front of the tube needs a feed from the cowl. The exit needs a
pipe to the cowl exit although it could be very thin. This is a
sealed style like Jerry Hey and Ed Klepis have come up with. On the 3 rotor
pipe the cool tube stops just inside the tailpipe. The section might be a
little confusing as it shows a small support bar that was suggested to prevent
the internal pipe from sagging. The sections I included should give a good
indication. The intent is to form a annulus that should draw air through the
tube venturi style. This needs only some clear space in front of the muffler.
The idea is that you should mix air in the tailpipe to A; cool the exhaust and
not burn the paint off the belly, and B; lessen the exhaust note by absorbing
some of the exhaust energy by mixing cooler air with the exhaust.
Bill Jepson