In E10 only 10% of the mix has 2/3 the energy of the other 90%. 1-2% is overly optimistic. 3-4% is more in line with published average specs of gasoline and ethanol.
I got an e-mail back from Huskey and they told me that my various questions (I asked lots) will be forwarded to the appropriate departments and that representatives in those departments will get back to me as soon as possible.
Eddie's post is correct. Other conclusions are an abuse of algebra
That's the theory of course. How the E10 blend affects one car vs another is likely subject to many other factors.
Here's a fun tidbit - look up "Saab Biopower". For a few years now in Europe they've had models that crank up the boost when the car is running E85 for significant increases in power. Takes advantage of E85's high octane.
We use alcohol [methanol] in the blown wheelstander.
It has high octane, but we need to DUMP a lot of fuel to get it to work. [compared to racing gas]
For E10 vs pure gas, the final result is the same - octane rating is octane rating. but there will be a hit on fuel economy.
Make no mistake, you need more volume of alcohol fuel than pure gas.
But not just lower MPG but much lower MPG with a 30%-40% loss depending on the source and possibly vehicle. There are better ways to slightly increase horsepower.
The Saab engine gets 20% more hp on E85 than regular gas. A non-turbo engine can't do much more than advance the ignition, for a small but much less significant increase.