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aerohead · 06-13-2009, 02:37 PM

The GM Sunraycer scored Cd 0.088 in the windtunnel and Cd 0.12 in full-scale race trim.The car originally had fairings fore and aft of the tire/wheels.That car was prone to lift,and when the nose took off,the area of the wheel fairings acted to turn the car sideways,which would dis-qualify it for competition when exposed to gusts from triple-trailer trucks in Australia.------------ Later,HONDA,with their Dream-2 Solar car,included the wheel fairings and the Drag coefficient fell to Cd 0.10.So the fairings can make a measurable difference.If your going to spend time messing around with this sort of thing I would encourage you to look at the Dream-2 and use it as your model,or Ford's Probe-IV concept car.-------- The flat panel as you see employed on contemporary cars has a drag coefficient of Cd 1.11 in free-air,and unless carefully sized in a windtunnel,as others have mentioned,you could easily oversize them,shooting yourself in the foot in the process.

06-13-2009, 02:37 PM	#23 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 15,895 Thanks: 23,972 Thanked 7,223 Times in 4,650 Posts	Extreme Deflectors The GM Sunraycer scored Cd 0.088 in the windtunnel and Cd 0.12 in full-scale race trim.The car originally had fairings fore and aft of the tire/wheels.That car was prone to lift,and when the nose took off,the area of the wheel fairings acted to turn the car sideways,which would dis-qualify it for competition when exposed to gusts from triple-trailer trucks in Australia.------------ Later,HONDA,with their Dream-2 Solar car,included the wheel fairings and the Drag coefficient fell to Cd 0.10.So the fairings can make a measurable difference.If your going to spend time messing around with this sort of thing I would encourage you to look at the Dream-2 and use it as your model,or Ford's Probe-IV concept car.-------- The flat panel as you see employed on contemporary cars has a drag coefficient of Cd 1.11 in free-air,and unless carefully sized in a windtunnel,as others have mentioned,you could easily oversize them,shooting yourself in the foot in the process.