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Old 01-07-2010, 12:18 AM   #414 (permalink)
3-Wheeler
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Quote:
Originally Posted by MetroMPG View Post
...Actually, the MPG change going from 45 to 35 mph in a Metro is pretty darn close to 15%!...
Hi Metro,

Thanks for pointing that out!!

Actually this should hold true for any speed above, let's say 10 or 15 mph or so, when the air pressure across the vehicle is dominant over the effect of Crr or rolling drag.

As the air velocity increases, it swamps out the Crr rather quickly since Crr is close to linear and air drag goes up as the square of speed, so the 15% improvement should hold true for most driving speeds.

Jim.
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