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Old 11-14-2009, 05:01 PM   #69 (permalink)
dluck
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Quote:
Originally Posted by Cd View Post
Um..........."insignificant" ??
Yes, insignificant for a car, not insignificant if you are peddling a bicycle. The boattail effectiveness is proportional to square of the speed. At low speeds where there is little if any energy being spent to push air out of the way, or sucking it back in behind you cannot get any benefit. Also the boattail length/curvature will create a sweet spot for a particular speed. If its not long enough there were still be drag as a vacuum is created behind the boattail. However being longer than necessary will start to add drag back and unnecessary weight.
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