Octane boost. My two cents
The numbers don't "add" for an simple answer. The 87 Octane fuel blend
of today is not the same as that of yesteryear. Too boost octane, lead
was added to gas to suppress knock by increasing octane (a reating based
on getting pinging in a very special motor with variable compression
(motor method). The amount of lead additive required depended upon the
chemistry of the fuel being enhanced. The simple fact is, that today's
87 octane unleaded gas is not the same as the 87 octane "leaded" gas we
used to get. It is a higher "grade", so it takes much less lead
addititve to get the results. Hence, the numbers don't appear to make
sense.
We used to mix the leaded regular and premium (only things available at
a gas station) to get "in-between" blends. There was a time when you
didn't even know what octane you were buying, only "Better" and "Best"
from each refiner, until the Feds required truth in labeling.
Again, about "how much octane is enough". If it doesn't "ping", it
doesn't need a better grade, and too much spark advance is too much, no
matter. You'd need greater than about 10:1 to require more than the
branded premium 92 can give you know. Most of the heavily advertised
addititves (and there are lots of additives in gas) are for keeping your
injectors small orifices clean. Tehnoline, by Standard/Chevron is among
the best, and can be bought without the gas. If you're using a Holley,
don't worry about it, the jets are very large, compared to injectors.
That is not to say that other formulation differences are not
important. The amount of "oxygenated" fuel added, and the amount of
alocohol, vapor pressure, etc., can greatly effect how your car runs. I
find that the Chevron/Standard seems to to a better job than others in
my Tiger. The tank I put in of "92" "Who Knows Gas Station" ran like
sh----.
Steve
--
Steve Laifman < One first kiss, >
B9472289 < one first love, and >
< one first win, is all >
< you get in this life. >
_/_/_/_/_/_/_/
_/ _/_/_/ _/_/_/ _/
_/ _/ _/ _/ _/ _/ _/_/_/_/
_/ _/ _/ _/ _/ _/ _/
_/_/_/_/_/__/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
_/
_/_/_/
|