Have searched far and wide looking for more information regarding this topic and it seems most people are not concerned with getting the most out of their combination in regards to torque, horsepower, and economy. My findings seem strange on the results i have been seeing while trying to get more miles per tank out of the motor. Its winter time so the mpg of gas goes down with the season so I am taking that into consideration. Right now i am around .82 EQR or 1.18 lambda or 17.1 AFR while lightly accelerating or cruising with e10. I have been using the method of lowest map to try to achieve the lowest map possible in my cruise areas and have been up to 64 degrees of timing with minimal gains. Does anyone know what the theoretical AFR value for maximum efficiency or lowest map is for e10 and were your results close to this value?