“ethanol is destructive to engines, especially small ones”
Spot On! I’ve had to resort to buying outrageously expensive clear unleaded fuel for my generator and other gasoline-powered tools. Ethanol is a poor motor fuel. While it has a decent octane number, it’s heat content per unit volume is a lot lower than gasoline.
I bought a bottle of something called Starbrite - Startron enzyme fuel treatment on the advice of my neighbor - a professional mechanic. He said it gets rid of the ethanol problems - I just started using it - so who knows?
You can extract up to 36% of the BTUs of ethanol, because you can run much higher compression and spark advance without even the smell of pre-ignition.
Gasoline ignition produces an explosion.
Ethanol ignition starts a flame front that burns more slowly through the power stroke, similar to diesel.