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aerohead · 10-31-2009, 03:31 PM

The October 1999 issue of MECHANICAL ENGINEERING has an article about the development of GM's 80-MPG Precept concept car.
During wind tunnel studies one of the 1/3-scale clay models came in at Cd 0.146.
In full-scale,and adding wipers,wheel covers,mirrors(cameras),door handles,and cut lines,the drag coefficient rose to Cd 0.163.
My guess,is that this is the Cd 0.14 model referred to.
Underfloor heat issues are solved by the rear engine layout ( yeah Preston Tucker,you're vindicated!) and the rear cooling solves the issue of the open nose.
I'll post a photo of the Precept when Al gets un-busy.
Also I have a pic of the Cd 0.18 Mercedes-Benz F300 research vehicle of 1997,which attained 100-MPG.

10-31-2009, 03:31 PM	#22 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,268 Thanks: 24,393 Thanked 7,360 Times in 4,760 Posts	I think I found the reference Really! The October 1999 issue of MECHANICAL ENGINEERING has an article about the development of GM's 80-MPG Precept concept car. During wind tunnel studies one of the 1/3-scale clay models came in at Cd 0.146. In full-scale,and adding wipers,wheel covers,mirrors(cameras),door handles,and cut lines,the drag coefficient rose to Cd 0.163. My guess,is that this is the Cd 0.14 model referred to. Underfloor heat issues are solved by the rear engine layout ( yeah Preston Tucker,you're vindicated!) and the rear cooling solves the issue of the open nose. I'll post a photo of the Precept when Al gets un-busy. Also I have a pic of the Cd 0.18 Mercedes-Benz F300 research vehicle of 1997,which attained 100-MPG.