>I'm not sure that's true.  Here in AZ I have bought gas at 7500' and it
>is still 87 octane for regular, while in NM, right next door, it is 86
>octane for regular, and this is true at a vide variety of elevations in
>both states.

The octane rating can be lower at higher altitudes.

The reason AZ gasoline is rated 86 or 87 is because the state resides
mostly at lower elevations, even tho an occasional mountain pass might
exceed 7000 feet.  In CO, UT, MT, WY, and other states that pretty much
reside above 4500 feet in most areas, the octane can be lower since nearly
all driving is at the higher elevations.

The gasoline is blended to for majority of the driving conditions.

Lower octane gas is not garbage gas. Using octane that is higher than
necessary is a waste of money.

John

>\> >
>> > I do have one peeve. What's with the garbage gas in Colorado? "Regular" is
>> 85 octane. Plus is what I consider normal for regular at 87 octace. Super is
>> 91, mostly (if available). Get me back to a civililzed state and decent gas!