Bill Freeman wrote:

Yvon,
Amoco Blue is their version of the  lowest octane fuel in the US,
and it rated by the Stupid, Moronic, Bureaucratic, bulls**t method
of averaging the Motor Method and Research Method of
octane measurement  (couldn't have made a *decision* could we?).

I believe that the number here at about 1000 MSL is 89 octane.
At higher elevations like Colorado (>4000 MSL) they use 87
octane for the std grade unleaded fuel.  There are two higher grades,
typically (from memory, may be wrong, I don't buy it) 91 and 93
octane (low altitude).   I assume the high altitude loss of BMEP
permits the use of lower octane fuel without pinging.

My engine is a Lyc O-235 C2C, which is a low comp
80 octane engine, and digests the "89 octane" just fine.
Don't know if the Motor or Research methods were the most
common years ago before the gov't waded in and muddled it,
or which might be used in other countries.  Apparently the two
systems were not dramatically different in values, but different
enough to need averaging.  Any octane testing experts out there?

Also, I use Amoco because they supported EAA's work in certifying
mogas for low octane certified aircraft, and Amoco is committed
to provide alcohol-free fuel.  Some US mogas has ethanol in it,
very complex BS tax-incentive stuff to help the farmers sell more
corn, but it significantly increases the vapor pressure and cuts
the margin to vapor lock.  Ethanol-free fuel is important.

Bill

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