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by bluGill 2867 days ago
It is more about the shift points in the transmission. Your engine is most efficient at around 90% throttle and "low" rpm. Your car is more fuel efficient are highway speeds then city street speeds (aerodynamic factors are insignificant at low speeds). The result is that engineers can trade acceleration for efficiency by changing the shift points, and you don't realize that the throttle is nearly wide open since the car isn't accelerating very hard at the low rpms.

Of course the engineers who design eco mode probably know more about how to do this than I do. I know they mess with shift points, it wouldn't surprise me if they did other things too.
1 comments
cmrdporcupine 2867 days ago
EVs have no 'shift points' or changing gear ratios.
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bluGill 2867 days ago
Maybe or maybe not.

Some EVs have a transmission - while it isn't strictly required (which is why others do not) for best acceleration you need one. If there is a transmission this is a shift point.

Of course EVs have completely different operating parameters. The rest of my post was respect to a internal combustion engine.

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cmrdporcupine 2866 days ago
Some EVs have a transmission, yes. My Volt has a planetary gear set in order to share traction with the ICE. But that's not a pure EV.

But what they don't generally have, unless they are conversions from ICE cars, is changing gear ratios. Torque is mostly constant across all RPMs in an EV, so there's not really a need for one.

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