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Discussion Starter #1
I came across this cool site:

http://www.race-technology.com/WebPage/Utilities/Coastdown/CoastDownCalcs.html

You can use coastdown values to calculate your cars coeffecient of drag! I did it twice and got values of .50 and .53!!!!! Man, parachutes on wheels!

NOTE: The value this program gives you is cD x area, you have to divide this value by your cars frontal area in METERS to get the actual cD.

This is by no means exact, but atleast it gives us a ballpark on how bad our cars are aerodynamically speaking. Have fun with it. And oh yeah, make sure you have plenty of flat road to do this on, it takes awhile to coast down when you are going slow.
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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Fits in with a statement made by one of the 60's Trans Am series racers who claimed that "At 150mph you hit an aerodynamic brick wall" (in a Mustang). Possibly Parnelli Jones, I don't remember, but the phrase stuck in my mind.
Thanks for the link. Hopefully at some point my car will be to the point where I can try it too.
 
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Back in my college days my aerodynamics professor asked on the first day what the most areodymanic car produced at the time was. He said the VW Beetle. Not sure if he considered all European sports cars of the day but when we thought about it all the lines of the Bug were smooth with clean airflow, thus his comment.
I always watch my hood pulling at the latch when I'm on the highway knowing its barn door affect. :(
 

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Beetle has relatively flat bottom, which is good in aerodynamics.
 

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That's why I didn't mind putting in lower gears that will restrict the
theoretical top-gear speed to "only" 145 instead of 170 as before...

Lo' actually turned 170 - on the dyno in March...
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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In about 1974 my brother discovered that if he got up to 85mph going down a steep hill, the front tires of his 63 beetle would actually come up off the road in the beginning of backflip much like racing speedboats are prone to doing.
Aerodynamics in action. ::
 
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