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Comment by Yaggo | Hacker News Reader

Impressive, but they are probably optimizing purely for burst power, not for efficiency, making the trick easier, because the car has an ICE delivering the base power. Compared to Tesla, they have to optimize for both power AND efficiency, because their car is running on sole battery power.

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If my back of the envelope calculations are correct, our 7-seater midsize SUV uses about 35hp at a sustained crusing speed of 70mph. For a road car being able to produce it's maximum power for only short periods isn't much of a problem.

Slightly different if you expect to be able to take it around a track.

Modern Teslas also can sustain max power as well. Model 3 can basically launch consistently 0-60 in about 3.2sec some 20-30 times with no loss. The new Plaid can do low 9s back to back until the battery is low. Quite an achievement.

And if you work for Tesla in the firmware department, you can get one that will do that backwards as well!

I know this is meant to be a joke but knowing folks that work in said department this is only true of engineering cars. They aren't able to do whatever they want with their own production cars.

The TLDR is production cars are "fused" at the factory to only work with firmware signed for production vehicles and devs can't produce these production builds themselves. There is facilities for live patching production cars but these systems are even more restrictive.

On the other hand... all bets are off in an engineering car. :P

So, they actually would download a car!

After 40mph the power of the model motor starts decreasing, it is linear but pretty steep.

As far as I understand, Teslas can't do multiple runs at highest performance level unlike Taycan.

I believe this was mostly on the older Model S that didn't have a dedicated coolant pump. It would always run at a fixed speed which was fine for normal usage but not on the track. New Tesla's have added a dedicated small electric pump so it can run at the speed needed to keep the motor in the correct temp range.

I'm sure they can still overheat based on other limitations (coolant radiator, pipe size etc...) but these can be rights sized based on trim level.

Quite right. The small graph in the article confirms it. If you zoom in enough you can see the power and torque are more than doubled during the 20second burst mode, but even so it is very impressive

I think Tesla cars also have a similar "burst" mode too?

Some turbocharged combustion engines also have something called overboost, allowing short periods of operation at higher power than the "continuous" limit (again due to heat build-up)

This might apply for the use in a car having ICE. The electric motor itself could be optimized for efficiency, too. Efficiency adds range and indirectly reduces weight by smaller batteries. To rate the efficiency, we would need more data about motor efficiency vs. loads.

Indeed, it's harder to deliver sustained torque, than sustained power.

Stall torque = current, and there is no trick around that.

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