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In city driving, if you don't drive EPA style you'll do better than the auto. In the city your engine is not doing anything a lot of the time, and the hydraulic pump on the auto will sap some energy. The gears are also closer on the manual so you don't lose as much energy spinning the flywheel/crankshaft/pulleys only to have the rpms drop for the next gear. 47 pounds less weight doesn't hurt either.
I looked it up, the EPA shifts at 15mph, and then 25mph, while accelerating at 3.3mph/s maximum...I went ahead and calculated how much load that was on the engine. 25% load...so they feathered the throttle to 3000rpm in each gear. No wonder they got 22mpg. Press down on the throttle halfway, shift anytime you want before 3k, you'll do much better.
This actually explains why sports cars have such horrible city fuel economy ratings despite being relatively lightweight. Since the EPA test has slow acceleration, a sports car's more powerful engine will be run at barely any load. High rev engines are hurt even more since the shift points are speed determined, not rpm. No wonder Mustangs and Corvettes force you to shift to 4th after 1st, otherwise they'd be posting more like 15mpg city. Imagine what happens to MT 911, the operator would have to barely touch the gas at all and rev to 3200.
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