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aerohead · 12-10-2009, 07:55 PM

there is an SAE paper which deals with "scatter" based on a single vehicle or standardized calibration models when tested in 6-or 8 different wind tunnels.
GM and Lockheed ( closed return ) results are the most conservative as far as Cd.
Ford publishes a yaw-averaged Cd ( they'll yaw the car up to 8-degrees in the tunnel )when they claim a Cd.
Is anyone saying if a uniform procedure was followed,to arrive at these latest numbers?
The mean standard deviation between GM,Ford,Chrysler,JARI,MIRA,Pininfarina,Canadian National Labs,etc., was only about 2.2%.

12-10-2009, 07:55 PM	#45 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,272 Thanks: 24,394 Thanked 7,363 Times in 4,763 Posts	Cd's there is an SAE paper which deals with "scatter" based on a single vehicle or standardized calibration models when tested in 6-or 8 different wind tunnels. GM and Lockheed ( closed return ) results are the most conservative as far as Cd. Ford publishes a yaw-averaged Cd ( they'll yaw the car up to 8-degrees in the tunnel )when they claim a Cd. Is anyone saying if a uniform procedure was followed,to arrive at these latest numbers? The mean standard deviation between GM,Ford,Chrysler,JARI,MIRA,Pininfarina,Canadian National Labs,etc., was only about 2.2%.