Quote:
Originally Posted by NeilBlanchard
Add the EV1 to that list. I think 3D shapes can achieve low drag with steeper angles than the ideal 2D shape?
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When the GM Impact made its debut in 1987,it's Cd 0.19 was a coup.
It's since been downgraded to Cd 0.21 by GM.
The same year,their Sunraycer was credited with as low as Cd 0.089 (with full wheel fairings).
This shape dates to 1922 when you lose the PV array
This is what Hucho talks about with respect to ultra-low drag aerodynamics.
In 1993,for their land speed record run at Ft.Stockton,GM lowered the Impact and stretched it,in accord with Hucho's recommendation for elongation
The Impact/EV1 LSR is credited with Cd 0.14.
She can go lower with more aft-body refinement.But she 'looks' like an EV1,and that's the point.
GM has been afraid of 'look-a-like' cars since 1923.Low drag cars all look alike when the Cds get low enough.This terrifies automakers bent on design obsolescence.
But back to your point.Cd 0.21 is not the same as Cd 0.08.Certain things have to happen with body architecture to get down there.And there isn't any way to cheat.