Don Foreman fired this volley in
:

Burning gasoline produces about 124,000
BTU/gallon, though some of that goes up the little stack.


That was the one thing that surprised me. I don't ever recall "trying
out" touching the stack when I was in nam. Last night, I did. It gets
hot enough to hurt, but barely hot enough to burn skin. It's pretty
amazing that they are able to extract that much energy from the fuel in
that simple an affair.

I also never remembered seeing more than one or two sections of stovepipe
on the ones in country. This one has eight feet of pipe. That will
increase the draft, and might add to the efficiency.

LLoyd