Quote:
Originally Posted by Occasionally6
In the context of:
If there is a choice between only having gears 1 and 3 (say) and gears 1,2 and 3, where ratios 1 and 3 are the same, and 2 splits them, three gears will allow the engine to be operated closer to its highest efficiency than will two of them.
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Yeah- especially if you're driving a tractor.
In the context of the real-world trip- for example when I go out of town- I'm accelerating through the lower gears for mere seconds then droning on for hours in top gear. With, say, 3 gears and a 0-55mph operating envelope, the engine
might fall outside of it's "perfect" rpm range for what- .001% of the trip? A minimally geared transmission that suffers less internal friction losses would be a fe benefit to me the other 99.999% of the time. Heck, maybe two gears would be enough... or a smaller engine (thinking of the 2.3 torque monster in the Tempo).
More gears maybe would have some benefit in trip scenarios heavy with urban, heavily loaded vehicle, or mountainous conditions... but I don't have those.
The act of shifting is itself quite inefficient: the flow of power and thus acceleration is interrupted, the throttle snaps shut and all the engine's whirly bits have to decel then "recel", similarly the flows in the engine's tracty bits have to slow then restart. Best to avoid that as much as possible, I think.