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Old 10-22-2012, 07:36 PM   #20 (permalink)
aerohead
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better at higher

Quote:
Originally Posted by Daox View Post
That rule of thumb is incredibly general. I don't believe it was intended with any specific speed relation. So, basically it says reduce Cd by 20% and gain 10% FE. Obviously you'll see better FE gains at higher speeds and less at lower speeds.
I believe that this is how it is,based on some of the published work.
And for 'noodling' purposes,I think it's okay to plot values for 55 mph and 70 mph,draw a line to connect them,then interpolate or extrapolate the percentage relationship to any velocity of interest as long as we don't stray too far from the known 55 and 70 data points.
If members will establish their baseline data at one or the other,or both velocities,it will make for a higher confidence when questimating.
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