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Old 10-02-2018, 03:47 PM   #20 (permalink)
ennored
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Quote:
Originally Posted by kach22i View Post
Thanks for posting the Cd, did you reference a source or just go off memory?
There's sources quoting "<.30". But as I recall, Bill Collins did extensive testing in a wind tunnel (U of M in Ann Arbor?) and later sent a full size vehicle for testing (at the Bendix Proving Grounds) which came in a bit higher than the model (as happens). Somewhere online is a complete history written by Bob, which he presented at an owners convention or something like that. I'll google that a bit more...

Also recall that the Vixen had a pop up roof, later replaced with a fixed, higher, roof, but that version wasn't aero tested.

So long as the front contours result in laminar flow along the top and sides, the length isn't as important. I bet a Vixen could be shortened quite a bit before the aero got worse. I think long bodies benefit from the air getting reattached along the length of the body. If it never detaches, it could be shorter.
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