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From: dcn@ihuxl.UUCP (Dave Newkirk)
Newsgroups: net.auto
Subject: Drag Coeff Information
Message-ID: <947@ihuxl.UUCP>
Date: Fri, 2-Mar-84 09:48:06 EST
Article-I.D.: ihuxl.947
Posted: Fri Mar  2 09:48:06 1984
Date-Received: Sat, 3-Mar-84 11:03:50 EST
Organization: AT&T Bell Labs, Naperville, IL
Lines: 12


	The drag coefficient is the total aerodynamic drag of a car divided by
its frontal surface area.  It shows how well a car is designed to reduce its air
resistance independent of its size.  Some cars that look very sleek have poor
drag numbers, such as the Porsche 928 (~.45) and the old Chevy Corvette.  Good
drag coefficients for new cars are between .35 and .4, and some are even lower.
	Graphs that depict all the sources of resistance to forward motion in a car
clearly show that air resistance becomes important at 40 mph and increases rapidly
with speed.  A low drag number also means reduced wind noise and better fuel economy
at highway speeds (as well as higher top speeds!).  But don't place too much
importance on the drag coefficient - it's only one way to improve performance.

					Dave Newkirk, ihnp4!ihuxl!dcn