[litesong]

I have 3 NA cars with many years of data with 87 octane 10% ethanol blends(E10), & many years of data with 87 octane 100% gasoline (E0). All 3 cars show mpg increases for E0 of 8%, 7% & 5%. All engines run smoother, quieter & with a trace extra low rpm torque, such that less downshifting is needed to ascend hills. 87 octane E0 is comprised of gasoline molecules averaging 87 octane(duh!). 87 octane E10 has ethanol molecules that average 114 octane of which 87 octane gasoline engines, as coming from the factory, are NOT designed to burn efficiently. ALSO, the gasoline molecules must average 84 octane, IF an average octane of 87 is to be created, while blending 10% ethanol. Yeah, even the 84 octane gasoline molecules aren't right for an 87 octane gasoline engine.

There is a difference of 3 percentage points in gasoline molecules, comparing 87 octane E10 to 87 octane E0, which doesn't include the ethanol difference. If your 87 octane gasoline engine isn't performing right with octane 87 E10..... try some 87 octane E0!!!

This is simple: gasoline engine engineers designed 87 octane gasoline engines to run best with 87 octane 100% E0. Ethanol engine engineers designed 114 octane ethanol engines to run best with 114 octane 100% ethanol. Ethanol/gasoline blends run neither gasoline or ethanol engines best.