Octane numbers

[Tom Tweed <ak627@dayton.wright.edu>]

The U.S. octane numbers listed on the gas pumps are a AVERAGE of the
Research # and the Motor # and are lower than the Research # alone.

I've had no trouble with Ethyl (NOT Methyl ! ) alcohol mixed gas, which
is the common Gasohol blend at 10% ethanol; I run 94 or 95 ((R+M)/2)
in the TR-250 with no pinging, no other (rubber) problems--after 8 yrs.

Best regards
Tom Tweed 
TR-250
SW Ohio