RE: Smallest gasoline engine?
Here is a brand new jewel: The .91 Webra 91-P5 Heli Ignition engine. Complete with pumped, regulated carb and electronic thyristor ignition.
Claimed power: 3 bhp (!).
Weight: 780 g = 27.5 oz. (presumably w.o. muffler)
Oil/Fuel: 1:20
Nice!
/Red B.