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Old 04-13-2008, 04:36 PM   #14 (permalink)
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Re the Prius "being the one to beat"...the Prius sure isn't my standard.

Sure, the Cd (of .26) sounds good. But, as you know, what counts is CdA. Wonder why you never hear what the Prius CdA is? Here's why: with a frontal area of 27.68 sqft the CdA is around 6 sqft! If you use an 84% factor on the LxW numbers, you get a CdA of 6.05; if you use 80% (which I really think is too low based on how boxy it is) you get 5.76 sq ft.

Compare that to the Honda Insight with a nearly identical Cd of .25 but with a CdA of 5.13 sq ft. Its frontal area (LxW) is 24.7 sq ft compared with the Prius's 27.7! (Note that the 5.13 CdA means that the true frontal area of the Insight is 83% of the LxW number which is one reason I think the .8 is probably too low).

And fer chrissakes--GM has the EV1 to build on and it had a CdA of about 4 sq ft. With a running start like that, there's no earthly reason for the Volt to be where it is.

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