Actually, grandma driving rarely helps.
High RPM + closed throttle = REALLY HIGH pumping losses. More energy is sapped maintaining a vacuum in the manifold than making power.
The only way grandma driving helps is high throttle at low RPM. It reduces pumping losses and maximizes the translation of fuel to thrust. The flip is that the engine is less efficient during low RPM than high RPM. Plus, it's bad for rod bearings.
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The Aggressive™ -- You don't know about it.
1998 Forester S - Big brakes, Big Tires, 5-gears.
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