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Cheben t1_j1igtpj wrote

They have basically constant torque (up to a point), but not power. Power output grow with rotational speed (power is torque times speed) , so the rated HP for electric vehicles can be extracted just before the torque drops of. A ICE also has low torque at low speeds, which is why they feel more sluggish to drive.

See here: https://images.cdn.circlesix.co/image/1/640/0/uploads/posts/2016/08/1682147d214d1e617551359320d2ee56.jpg

Electric peak power is at about 2900RPM there

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max_p0wer t1_j1ish12 wrote

Any “constant torque” would be due to the fact that at low speeds you’re traction limited so only a fraction of the cars power can be used.

Once you’re no longer traction limited, the torque will steadily decrease and power output will be flat.

This is a Tesla S P85D on a dyno. Notice the torque peaks (at 864 ft-lb!!!!) then steadily decreases. The power is nearly perfectly level just above 400hp for the entire second half of the run.

https://www.pinterest.com/pin/297096906643419592/

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