Thread: VW Reality
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Old February 6th 08, 09:28 AM posted to rec.aviation.homebuilt
oilsardine[_2_]
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Default VW Reality

the modern 'VW engine': http://www.ulpower.com/

"John" schrieb im Newsbeitrag
...
Charles Vincent wrote:
RST Engineering wrote:
I could be very, very wrong, but my understanding of efficiency is that
25% efficiency means that a quarter of the energy goes to torque and 3/4
to heat. That would mean you throw away THREE horsepower's-worth
instead of four, no?

Jim



since such engines are no more than 25% efficient when it comes to
converting the heat of combustion into torque at the crankshaft. That
means that for every horsepower measured at the crank you must
generate at least four horsepower's-worth of heat in combustion.


You are correct, but that is also exactly what he said ---. i.e. generate
four hp in heat, only one available at the shaft.

Charles



Well that's better than a 100 watt electric light bulb, which is a 90 watt
heater and 10 watt light source...

John