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Old 07-07-2008, 10:27 PM   #52 (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)

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90 day: 125.37 mpg (US)

U.F.O. - '00 Insight
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Quote:
Originally Posted by .Cd View Post
Both you and I have a rounded tail end to our cars.
I'd guess that they are rounded for a reason, but as we know, a sharp edge is usually better than a rounded end.
I'm not sure you can get any useful info from doing a tuft test comparison of the two styles. A sharp cutoff of a proper taper will simply show the tufts streaming straight back before the cut. A radiused cut off will show some turbulence after the separation point on the curve.

I never did get a good answer to "which is better" after that long thread at GS. It's something I'd like to talk to a pro aerodynamicist about if I ever meet one.
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