All of the examples you cited require an extremely high compression ratio,
something our Spitfires do not have. Diesels ~ 20:1 and extreme race
engines, pumped with 30 lbs of boost. There is a balance required, too
slow a burn and the combustion process is not complete when the piston gets
to the bottom of the power stroke (wasted energy), too fast of a burn and
the result is engine damage (detonation). The best is to have a controlled
burn process that is completed right before the piston gets to the bottom of
the power stroke. High compression engines require a slower burning fuel
(high octane) so they do not detonate and do sever engine damage. Low
compression engine need a faster burning fuel to achieve max power (to a
point). Low compression engines can run on high octane fuel but the only
benefit is a lighter wallet (I guess thats less weight in the car to pull
around - faster acceleration).
MikeC
>of the reasons why fuels like diesel, methanol and nitromethane make so
much
>power (its not quite THAT simple, but these are slow burning fuels). Rapid
>burning fuels push on the piston for a short time on the downward storke,
>hence no power. Just my 2 cents and awaiting my change.
>
> Michael
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