High altitude, and low octane

[Brad Wilson]

Living in Colorado, we get 85, 87, and 91 (US-rated) octane fuel, rather
than the traditional 87, 89, and 93 (though some sea-level gas stations use
91 octane for their premium).

Apparently, one of the local TV stations, KOAA[1] in Colorado Springs,
had an exposé last week about this. The traditional story goes: the higher
you go in altitude, the lower octane fuel you require. They claimed that
while this is true of carbureted(sp?) engines, it's not true for fuel
injected engines. (Of course, the major source of controversy here, too, is
that we're paying more for 85 octane than others pay for 87, but that's a
separate issue... just saw $2.10 for 91 octane today).

So, I figured this list probably has at least 1,000x the brain power of the
average TV investigative reporter, and before I passed on the "electronic
petition" link to all my friends, I thought I'd get the scoop.

The $64k question: for fuel injected cars, do you want lower octane fuel for
higher altitude, or the same octane as cars that run at sea level?

ObAudiRef: I always use 91 octane. =) And there are occasional stations
around (_very_ hard to find, and _very_ expensive) that offer 93 octane fuel
here in the "high plains".

Best regards,
Brad

[1] http://www.koaa.com/

2000 A6 2.7 biturbo quattro   http://www.quality.nu/bradw/audi/
2 turbos, 1 driver ... no limits