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[quote cbelt3]I drive a stick...basically driving the way I ride my bicycle
Those are the secrets right there.
If you haven't been on a bike in awhile, do it. You'll gain a deep understanding of the relationships between terrain, wind, speed, acceleration, gearing, and energy expenditure.
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when waiting in line at a drive through, at what point does it make sense to cut off the engine? if the wait is more than 30 seconds, 1 minute, 3 minutes?
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Typically 12 to 15 MPH here. 0 gpm.
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Should it be voluntary or should we clamp down interstate speeds again? Not that many actually observe a posted highway speed limit.
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Reported gas mileage improvements in this thread suggest a reduction in gas usage at 65 mph to 80% - 85% of the usage at 75 mph.
At higher speeds wind resistance, aka aerodynamic drag becomes the dominant force, but not the only force, a car must overcome to maintain a constant speed. Wind resistance is equal to a constant x speed x speed, where the constant is a function of a cars shape and the local air density.
Plugging and chugging shows there is 75% as much aerodynamic drag to overcome at 65 mph compared to 75 mph, i.e., 0.75 = (65 x 65) / (75 x 75), which compares fairly well with the 80% - to 85% reported in this thread.
"Should it be voluntary or should we clamp down interstate speeds again? Not that many actually observe a posted highway speed limit."
IMHO - Voluntary
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my GSX has the same fuel economy at 60 as it does at 80.
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my Z-28 used to get much better mileage in town than on the highway.
For some reason the mileage dropped to about 4mpg whenever near Epping N.H. :-)
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The comment about cars zooming past you (sometimes unsafely) and only gaining a few car lengths has been my experience too. I suspect the main benefit of driving faster than flow is psychological.
Not too long ago, I think someone on this forum quoted George Carlin as saying, "Have you ever noticed that people who drive faster than you are maniacs and people who drive slower than you are morons?"
