This is straight from the Cummins web site and it explains why a diesel
engine puts out more power than a gasoline engine. Has to do in a great part
due
to the BTUs of the different fuels. I find this very interesting!!
Fuel BTUs. "The btu value of diesel is greater." Quite true, the btu, or
British thermal unit, for diesel fuel is 130,000 btu's per gallon and a weight
of
7.4 lb/gal. The value for gasoline is 117,000 btu's and a weight of 6.0
lb/gal. If we go back to our basic physics rules for energy, you'll note the
fuel in
the tank has potential for work if it is injected into the cylinders
and, combined with the compressed heated air, ignited. The piston is forced
downward,
the crankshaft rotates, the wheels turn. The diesel design (the "heat
engine"), compression ratios (the "heat engine"), the fuel injection system
(allowing
85:1 down to 25:1 air-to-fuel versus gasoline at 14:1) and fuel btu's (diesel
fuel has more power), all these diesel attributes add up to more miles per
gallon of fuel!
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