[bwilson4web]

Originally Posted by Phantom

I read a while ago that blends between 20E-45E could actually give better MPG but the amounts differed on different cars. I cannot find the original pdf it might be at home but a quick search came back with:
http://www.ethanol.org/pdf/contentmg...yStudy_001.pdf
http://www.ethanol.org/pdf/contentmg...se_12507-1.pdf
*This is bias due to the author of the study but I was thinking that the other document I had found was from a different organization but I could be wrong about that.

Those were the papers that motivated me to study E30 in the Prius only the results were so modest and the savings so small, the labor it took to 'home brew' E30 didn't make sense. That is why I came to the conclusion that it might be useful but the margin of error was too large and I didn't see a clear, winning strategy involving E30.

But I also think it is important that results are vehicle specific and the engine control laws have a lot to do with whether or not it can 'tune' to optimize performance either on a miles/gallon or the riskier, $/mile.

Now this is pure speculation but it may be possible that a properly tuned, Atkinson cycle might be able to exploit a higher, effective octane rating of alcohol blended fuels to improve efficiency. I do know at maximum power, my 1.5L Prius engine will 'tune' to exploit 93 octane gas in a maximum power, hill climb. But it isn't clear that this could be achieved at less than maximum power.

GOOD LUCK!
Bob Wilson