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Old 10-03-2011, 11:14 PM   #338 (permalink)
redyaris
Master EcoModder
 
Join Date: Jan 2010
Location: Alberta Canada
Posts: 744

redyaris - '07 Toyota Yaris
Team Toyota
90 day: 45.54 mpg (US)

Gray - '07 Suzuki GS500 F
Motorcycle
90 day: 70.4 mpg (US)

streamliner1 - '83 Honda VT500 streamliner
Motorcycle
90 day: 75.63 mpg (US)

White Whale - '12 Sprinter 2500 Cargo Van
90 day: 22.01 mpg (US)
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Quote:
Originally Posted by darcane View Post
Actually, it isn't...

Plain and simple, efficiency is a ratio of output to input. Horsepower and torque don't describe a ratio, and thus aren't efficiency ratings. In general, increasing volumetric efficiency will increase horsepower and torque, but that doesn't mean the latter are efficiencies.

BSFC is a measure of efficiency since it is a ratio of output (brake power) to input (fuel consumption).
Power = work/time, a ratio
Torque = force x moment arm, not a ratio
BSFC = fuel used/torque, if I am not mistaken, a ratio

The word "efficience" is a catch all for everything good in society... and as you suggest it is too often misused.

For us the ratio is Fuel Economy = distance traveled/volume fuel consumed, a ratio

For Craig Vetter the ratio is Economy = $ for fuel/distance traveled...

Last edited by redyaris; 10-03-2011 at 11:34 PM..
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