Here in TN we have stores called Weigel's. They actually sell true 87 octane which in my Patriot nets me about 28 mpg vs 26 mpg for ethanol based 87. My question is this: is a true 87 octane gas better than say a top tier 87 with 10% ethanol?
atikovi said:Yeah but more often E-10 us really E-6 to E-7 and E-85 is around E-65 so when people post 20% difference in fuel economy with E-10 vs E-0 it's not the fuel. It's either driving conditions and or the poster fudging logs, math, and or improper pump readouts because the BTU difference isn't there.
The base gasoline itself can have a range of energy content per unit volume. I heard maybe up to 2% difference between different blends. And it's not easy to control the energy content since there are a lot of factors including the source crude oil.