Originally Posted By: purelux
It simply does not produce as much energy and those minute "gains" are within a margin of error. Those figures come from gm not an independant correct? E85 benefits farmers, and well thats it. Its more expensive if not govt subsidized and if a car is flex fuel it is comprimised to use regular or e-85 if it were one or other it could be better optimized.
I'm not even about to try and "justify" E85, I agree with you as it is currently produced.
However, the energy per gallon is not the same thing as the HP created by the engine in question. I agree with you that the E85 has less energy per gallon, but as you hinted...it's all about the tune. It takes more E85 to get that HP, hence the lower MPG, I'm not saying the marginal gain doesnt come with an added expense. But it is there. From what I've noted in reviews an E85 engine with a proper tune to utilize it, will usually put out more HP than the same engine optimized for E10. But hey, if you want dyno slips....I'm outta luck.
Really though, what incentive does GM have to lie about a number that makes sense if you think about it. All kinds of engines make insane HP from similar alcohol fuels all the time. Curious....What is the margin of error for a good dyno? You said those numbers were within that margin, the 2.2 eco gets 8 FtLbs more TQ with E85. Thats better than a 5% gain, how innaccurate are dynos exactly?
ftr, the numbers were quoted from Car and Driver....but I'm sure you are right, they ultimately came from GM.