So a station near me sells E30 at the pump. I decided to fill 7/8ths of a tank with E30 to see how it does. E30 has an octane rating of 94.4. I can say the butt dyno reports a very noticeable improvement in response and power. I don't know if it is placebo or real, or some combination of both, but it does seem to have more power and is generally more responsive. No CEL, no downsides or side effects that I can determine. Traction control comes on through 3rd gear on demand. Figure that I had 2 to 3 gallons of 93 octane in the tank, the E30 probably blended down to something like E20 anyway, so not much above the E15 that is factory approved. I wonder if the factory tune has any KR with standard gas, or if the ethanol blend provides for some cooling effect to enhance performance. It would be great if the factory tune was secretly E30 or E85 enabled, but I doubt the fueling system is adapted for high ethanol %.
Another thought - Ex blends have less energy density (hydrocarbons) than regular gasoline, so running Ex without an adapting tune effectively, stoichiometrically, leans the fuel mixture. Less fuel C-H per O2 per fuel unit than gasoline. So wouldn't that effectively run hotter and more thermodynamically efficient, and more power, particularly under boost?
Another thought - Ex blends have less energy density (hydrocarbons) than regular gasoline, so running Ex without an adapting tune effectively, stoichiometrically, leans the fuel mixture. Less fuel C-H per O2 per fuel unit than gasoline. So wouldn't that effectively run hotter and more thermodynamically efficient, and more power, particularly under boost?