OK explain this to me someone. You're going 70 mph, 2500 rpm, you get 25mpg. You're going 70 mph, 2500 rpm, headwind of 20 mph. Engine revs the same, same gear, same amount of air goes in the plenum, fuel economy goes down coupla mpg's. Why?

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You don't need a weatherman to know which way the wind blows - Robert A. Zimmerman