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Old 03-15-2009, 10:11 AM   #15 (permalink)
MetroMPG
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Metro
Team Metro
90 day: 67.07 mpg (US)

ForkenSwift - '92 Metro EV
90 day: 125.37 mpg (US)

U.F.O. - '00 Insight
Team Honda
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Quote:
Originally Posted by Bicycle Bob View Post
Getting the air to part is like pushing a pen through a sweater
Yes, but are we talking about a pointy pen tip or a blunt one?

Quote:
Originally Posted by hypermiler01 View Post
There are some who focus strictly on Cd and seem to ignore air pressure
Could you please explain what you mean by this a bit more?

The measure of air resistance ("Cd") is inherently about pressure - pressure drag comprises the largest fraction of drag a road vehicle encounters.

So a vehicle with a low Cd is better at "managing" air pressure than one with a high Cd. It isn't possible to talk about drag coefficients of cars and "ignore" air pressure.
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