Well unless you have $42 to buy a copy of D5798 from ASTM, you can't readily find out what the rest of the specs for E85 must be. ASTM says E85 can be anywhere from 51-83% ethanol. Presumably it would be gasoline, but who knows - it could be any of a myriad of hydrocarbons. From what I can tell, the only thing specified is that it must be a hydrocarbon. Since you were involved in an EPA study, could you help us out?
As far as ehtanol's benefits over gasoline, it is the fact that it reduces detonation. The reason that it reduces that detonation is that 1) the ethanol molecule contains an oxygen atom that aids in the burning process, and b) more of it is required to burn, which increases the heat absorption as the fuel vaporizes for burning.
I agree with you that E70 should be able to handle way more than 10psi boost. I'm wondering how you come to the conclusion that E70 can handle more boost than E85. I guess the quality of the gasoline in the mixture would be the deciding factor given all other aspects would be constant (same motor, ambient temp, humidity, etc.)? But if this is the case, how can you determine the quality of the "rest of the E85" without doing some sort of "non-feasible" chemical analysis on a sample every time you fill up?
