Quote:
Originally Posted by Nixlimited
Ethanol has significantly less potential energy than gasoline. That's why it takes significantly more of it (think huge injectors) to make lots of power. But it's excellent for knock resistance.
Per Wiki: Gasoline has 114K BTU/gal to Ethanol's 76K/gal. |
I think the key value here is latent heat of vaporization vs. amount of fuel needed to achieve peak torque, which is a factor related to stoichiometry -- check out p. 117 on down at this link.
http://martysgarage.info/manuals/bell2ttuning.pdf
It's from A.G. Bell's book on fueling 2-stroke engines, but he has the exact same formulas/rationale in his 4-stroke supercharged tuning book.
Anyway, in theory, less efficient, but more energy ultimately produced as a consequence.
Now, if E85 ends up breaking about even, then it's just less efficient, but has a higher auto ignition threshold and higher octane, in which case never mind my other point
