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Old 01-07-2008, 07:00 PM   #38 (permalink)
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Airdam or Airdamned?

One thing that I feel hasn't been discussed too much yet about airdams vs. bellypans is the point of diminishing returns.
So far we know (at least in theory) that a bellypan is better because of the lower frontal area, and also the probable decrease in Cd from all the hanging bits on the underside.

But what we don't know is how much better a belly pan is. Has anyone seen any data on this so far? The most relevant thing I've found so far has been this refrence (PDF file) to a 1958 study
"Hoerner 1958 discusses the underbody as the biggest single avoidable
aerodynamic drag component and gives an old example where drag goes
from 0.3 for a smooth underbody to 0.6 for an open and rough as
customary car!"

Still no word on how much an airdam would knock off that 0.6

So, I hope eventually when I do get myself a jack, some jackstands and a new (working) drill I can get a belly pan together to test it out and get some numbers.

This list of things to do is getting quite long.
"I got 350 heads on a 305 engine. I get 10 miles to the gallon. I ain't got no good intentions." - The Drive By Truckers.

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