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Old 05-22-2008, 09:21 PM   #10 (permalink)
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Very clever device you created. I like the sleek way you integrated it into your dash.

Originally Posted by Gregte View Post
I have always thought that pressing the accelerator pedal down further, as required in higher gears, was worse for mileage, but I am surprised to see how that is not quite true.
I think one of the most useful concepts in the world of hypermiling is P&G. And I think the essence of P&G is large throttle settings. They are more efficient because they minimize pumping losses. But this is perversely counterintuitive.

More on this subject:

Monitoring instantaneous consumption is helpful, but I think it's fundamentally important to not be misled by the short interval of measurement. In P&G, you spend extra fuel now in order to save fuel later. The fuel has been converted to kinetic and potential energy that you'll soon call on (while gliding).

Focusing only on lowest instantaneous consumption is at odds with maximizing efficiency. It will guide you into a steady cruise, which is less efficient than P&G. Maximizing efficiency requires a broader interval of analysis, like a trip, or at least portions of a trip. Because your analysis has to encompass the entire P&G cycle, as a complete unit.
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