racers see Aviation Gasoline (Av Gas) as
a way to reduce the cost of their racing
operation. This may be true, but if you
want the most out of your engine and want
to avoid problems, Av Gas may not be your
first choice. Av Gas is a good gasoline
for low speed aircraft engines that run
at 2700 to 2800 RPM at 10,000 feet or higher.
This does not mean it is a good gasoline
for racing engines operating at 8,000 to
10,000 RPM. Av Gas is also illegal to use
in anything except aircraft engines. Violations
can carry a potential penalty of $25,000
per day of violation.
Gas octane numbers are determined in a different
test than motor gasoline octane numbers.
Do not be confused by the big numbers from
the Av Gas test method. They are not comparable
to motor gasoline test numbers. The 111
octane version of Rockett Brand
Racing Fuels tests at 160
on the Av Gas scale.
Gas is held to tighter requirements than
street gasoline, but not nearly as tight
as is the entire line of Rockett
Brand Racing Fuels. Some racing
gasoline blenders use Av Gas as a blending
component to save money. For Rockett
Brand Racing Fuels, we do
not. We use only the highest quality components
since Av Gas is far too inconsistent to
use as a blending stock for Rockett
Brand Racing Fuels.
Gas has a lower specific gravity than most
racing gasolines. This means that if a racer
tries Av Gas and has not re-jetted, he can
burn a piston because the air-fuel ratio
is too lean and/or the engine detonated.
To make a good comparison between two gasolines,
the air-fuel mixtures must be the same.
Even after re-jetting, the racer can experience
burned pistons with Av Gas if the Motor
Octane Number (MON) is lower than what his/her
potential problem with Av Gas is that there
are several different octane grades. The
80/87 grade is red in color and can get
you in lots of trouble because of its very
low octane number. The 100LL is blue and
the 100/130 grade is green. Both of these
have much lower Motor Octane Numbers than
most racing gasolines and will detonate
when the engine octane demand is greater
than the octane number of the gasoline.
bottom line is: Feed that high dollar racing
engine a good grade of gasoline so it will
deliver the maximum performance for you.
Don�t use �low bidder� mentality. This is
not the space shuttle.