I realize this is off topic as well, but perhaps of higher interest.
It pertains to testing of 94UL in a Continental.

http://www.flyingmag.com/piloting/1865/flying-a-big-bore-engine-without-the-
lead.html

One comment in the article near the end I would question is this one:

/"Of course, because 94UL is lower in octane than 100LL, its potential
energy will be lower across the board, regardless of whose engine the
future fuel is being used to power."/

High Octane provides a slower burn rate, but caloric value should be the
same regardless of Octane number.
What is the general consensus on that?

Rolf

ON AVERAGE (as quality does vary with refineries, batches and seasons), 94UL
actually has a slightly HIGHER calorific content than 100LL (if it does not
contain a percentage of ethanol).  The main reason is the higher
concentration of additives in 100LL than in 94UL, additives which brings no
energy to the fuel mix.  However, as 100LL is much more detonation
resistant, it tolerates higher compression and/or boost ratios resulting in
higher overall engine efficiency.

Conclusion:  if an engine can accept low-octane fuel (such as the rotary),
then it will get (slightly, i.e. 1-4%) better specific fuel consumption with
94UL than with 100LL.  If the engine cannot accept low-octane fuel in its
existing definition, then its performance envelope has to be reduced to
accept it.  The quoted statement is fundamentally flawed.

Francois


Are you in Copenhagen? I am curious on what is going on there.

Paul Lamar

Hi Paul,

No, I am not in Copenhagen.  I have too much work getting our company off
the ground to go there.  However, I follow what's going on quite closely as
it will undoubtedly have a strong influence on our business.

BTW, a friend of mine is working for a large car manufacturer in a
management position within their fuel-cell car development.  I visited him
in Germany some weeks ago and got to drive one of their fuel-cell powered
prototype.  Awesome!  Performance is great (you would need a big-bore
gasoline engine to match it), the car is extremely quiet (actually they will
have to generate some kind of artificial noise so that electric cars can be
heard coming by pedestrians), nice, simple and comfortable to drive.  Of
course, the manufacturing cost of fuel cells is still astronomical but they
are working on bringing it down.  Operating costs are a fraction of a
similar-size gasoline model.  Who will need oil?  ... well, aviation for
quite some more time, of course.  The Saudis are getting worried and have
floated the idea that oil-producing countries be compensated for the oil
they won't sell (good thing for them that ridicule does not kill, as we say
in French), I love it!  No matter the climate dispute, the technology is
just plain so much better... a quantum leap.  Those who will not develop
those "clean" or "cleaner" technologies and gradually replace fossil fuels
will plain and simply miss the opportunity of the 21st century.

VBR, Francois


That is interesting. Back in 1978 I was working with these guys from LASL who where working on fuel cell powered vehicles at the time.

Microprocessor-Based System for Roll-Down and Acceleration Tests
by D.K. Lynn, C.R. Derouin, and Paul Lamar
Los Alamos Scientific Laboratory
Published in IEEE Proceedings 29th Vehicular Technology Conference
(The technical details of the road test system.)
Arlington, Illinois, March 28-30, 1979

Things are not progressing very quickly on this technology.

Paul Lamar