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Comment by nostrademons | Hacker News Reader

At that speed the limiting factor likely moves from raw power output to things like cornering ability on the track, grip of the tires, aerodynamics, downforce, driver skill, mechanical linkages, etc.

There's a reason why all the world's land speed records since the 1930s [1] get set at the Bonneville Salt Flats or similar flat desert terrain. FWIW, the speed listed in this article was exceeded in 1937. The hard part is not necessarily going fast, it's going fast in a street-legal vehicle.

[1] https://en.wikipedia.org/wiki/List_of_land_speed_records

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For a top speed run, cornering ability is next to useless. You need grip to put down the power and be stable at speed, the corners taken for top speed runs are fairly wide. The bigger issue here is for how long can a BEV sustain max power output - it can deplete its battery in 2 minutes. EVs also can only produce top power whilst battery is at top voltage, since draining it drops voltage, max power drops with charge levels. The tyre grip itself is fine, the issue is tyre durability - they can usually last less than 20 minutes at top speed.

It is an impressive feat of engineering to get to a vmax record in a BEV.

I'll need evidence of "Top power at Top Voltage." Since so little capacity is at that part of the curve, It'd make sense to design around (as in avoid, not feature) it rather than use it.

I suspect theres inductance and capacitance enough that even if the motors can't handle the voltage, it can be "clipped" until the pack comes down. (Especially since fmu these are 3phase AC motors, the motor driver is already regulating voltage and current to produce whatever the optimal waveform is)

Well you can see reports of people drag stripping teslas, and comparing speeds at 100 vs 90 vs 50% charge. Whatever the reason, you do slow down.

Apples to broccoli comparison. Besides what I mentioned being optional (I'm sure it has downsides, probably cost), comparing road legal cars with a supercar is... interesting.

You don't need a Tesla to figure this out, my toy RC monster truck does the same thing.

You don't need to design around it - it is not like you can use top power for 100% of the time in most EVs anyway, and there's no good reason to restrict it such that the vehicle can operate at a limited max power for longer. ICE cars also reach top power only in a given RPM range, so it still is a curve, albeit turbo cars can flatten the curve quite a bit.

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