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Old 06-12-2009, 11:27 PM   #21 (permalink)
Otto
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Quote:
Originally Posted by skyl4rk View Post
Thats new to me. Why does the air flow in an angle, if the car is going straight? Pressure from the front end of the car moving to the outside?

Bow wave off the nose flows laterally around the front of the car, and if unfaired, the front wheels act as a flow fence impeding the bow wave, creating drag.

The oblique angle is greater than I would have thought, until studying a photo in the Hucho book, showing a smoke stream around the front of a Calibra (I think). In that pic, the smoke stream angled about 60 degrees outboard from centerline. Maybe somebody with Hucho who can post pics can find and post it here for us.

For your car, tuft testing would be cheap and easy. Perhaps the tufts could be mounted on inverted Ts 2-4" under the nose, so visualize flow several inches below the body, as the air moves rear toward and around the front wheels. Then, set the incidence of the deflectors accordingly.

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