said by nunya:I never said the higher octane rating improved my mileage. The lack of a lower potential energy density fuel mixed into the gasoline was probably the reason the mileage increased.
Another victim of the octane myth.
Your vehicle is designed to use Regular unleaded gasoline with pump (R+M)/2 octane rating of 87.
Higher octane doesn't improve mileage. It reduces early detonations (knock). Sorry to poop on your parade.
If you want to buy regular gas and just send me the extra $.30 per gallon, I can guarantee you the money would be better spent. I'd at least mail you a Christmas card every year.