On Mon, 26 Apr 2004 13:16:54 -0400, "George A. Graham"
wrote:

The BSFC of the Mazda wankle can get as good as .42, where the Lycoming
is over .5, and the turbo diesel is best at .36 lbs/hp/hr.

I am aware that most people should avoid trying to craft their own
airplane engine, but if you are so inclined, the Wankle rules!

Hey George, good to hear from you. The Lycoming engine can get as low
as .38 BSFC when properly set up. Few pilots seem willing to go there
though as it requires leaning past peak. See John Deakin and "Mixture
Magic" in the AVWeb columns. The GAMI folks demonstrate the above
fuel burn routinely on their test stand. Auto engines tend to be at
..42 as you mention. I think lower BSFC with the big bore aircraft
engines has to do with large pistons and long stroke, I think, not
absolutely sure.

I'm getting set to do the ground runs on my engine and intend to run
it throughout the summer at high power settings. I don't understand
people who just bolt an engine, any engine, to the airframe and then
try to go flying without any test runs.

Corky Scott