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Re: Coke-bottle shapes, etc.

To: <BWANA343@aol.com>, <zoombot@cox.net>, <land-speed@autox.team.net>
Subject: Re: Coke-bottle shapes, etc.
From: "Ed Weldon" <23.weldon@comcast.net>
Date: Sun, 29 Apr 2007 10:37:52 -0700
OK you guys.  Time to get your feet back on the gound.  The king of the
aerodynamics factors is frontal area.  All these other streamlining issues
are just a bunch of court jesters. (tickle, tickle......that should get'm
all stirred up.)

Do you know what your frontal area is? OK, if you do you may not be
interested in what's below.  If your car is a brick, like a street roadster
(OK, Rocket Science with the '34 body is at least trying) or a stock body
there's not much fruit on that tree.  But others up to special
construction....that's where it becomes important.  It's probably a good
thing we can't easily measure frontal area or there would be a lobby to add
that complexity to our class breakdowns. (more tickles)

But wait!!  Anybody out there know what a planimeter is?  It's an arcane
drafting tool little known outside the world of professional draftsmen or a
few scientific disciplines. It's used to measure irregular areas usually in
square inches.  Do a Google search on that word.  Search ebay and you'll
find old mechanical planimeters selling in the range of $20 to $60.
For our application get a frontal view of the car.  In the absence of a
scale drawing use a photo.  Get your longest telephoto lens and get  as far
away from tha car as you can and still be able to fill the viewfinder frame.
This reduces the perspective effect that would shrink the size of the rear
parts of the car.  Before you snap the photo put something of known length
in the scene that you'll scale the picture off of.  Don't forget to read the
instructions on how to use this new gadget.
Ed Weldon




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