Bill and Doc,


      So the bottom line is that all of the oxygen in ethanol is available
      for oxidation. That is why an engine running on ethanol makes more
      power, even though the heat energy in the fuel is lower.

      The reason is that the extra oxygen in the ethanol allows you to run
      a richer mixture, thereby adding more carbon and getting more total
      heat.
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I agree with all the discussion of oxidation.  Very well explained -  until
we get to this part.  While true, by itself, it is misleading. The engine
will make more power, but only at a higher fuel burn; even for the same
power at the low altitudes it will take a higher volumetric burn. Isn't the
bulk of the power coming from oxidation of the carbon, and there are fewer
carbon atoms per gallon of ethanol? Yes; at higher altitudes where there is
less O2 available in the incoming air, the ethanol can have an advantage.

Or did you already say that?

AL

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I have to work more on my reply, but the oxygen in ethanol is NOT
(I believe) available for oxidizing the carbon or hydrogen in the
ethanol. The oxygen in ethanol has already been reduced, just like
the oxygen in water (H2O) and is not available to combine with either
Carbon or Hydrogen.

Nitromethane and Nitrous, are a different story. The oxygen is tied
to a nitrogen, the bonds are different, and the bonds can be broken
by catalysis or heat and release the oxygen for combination with the
primary fuel. They truly do bring the oxygen into the combustion
chamber in the form of a liquid fuel.

It will be a few days before I can get to my reference books to be
able to explain it. If I become convinced that Gordon is right, I
will certainly say so, but I believe that the increased POWER effects
of ethanol and methanol are due to something other than that they
are carrying Oxygen into the combustion chamber.

Bill Schertz


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