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Old 04-27-2012, 05:26 PM   #12 (permalink)
aerohead
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Quote:
Originally Posted by Regenerit View Post
I'm seriously questioning this reasoning, if the air dam is low enough to increase CdA beyond the lowest part, wont it also help to decrease the car's drag by limiting the amount of air that goes under the vehicle, despite it going past the lowest component?

And additionally, isnt CdA measured from the bottom part of the wheels up to the highest point in the car?
The frontal projected area is measured from the shadow of the car cast perpendicularly on a wall directly behind it,from a parallel light source as the sun,or laser,from directly in front of the vehicle.
If 'protruberances' (mirrors) are on the vehicle when tested,they're frontal area cannot be included in the 'official' frontal area for test purposes according to the EPA rulebook,and the vehicles Cd will be artificially higher do to the unaccounted area.
The Cd will be based on actual test measurements,whether from coastdown,or from wind tunnel.
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