Model S Dyno Chart: 4,300+ Torque, Linear HP

Dyno chart! 2,000 ft/lbs, which is apparently the maximum this dyno can read, lol. Obviously an error but look at that curve… or lack of a curve.

http://www.dragtimes.com/blog/tesla-model-s-confuses-a-dynojet-dyno

they really fudged the hell outta that dyno run…the torque is being multiplied by the factor of 9.71 because of the lack of a 1:1 gear ratio. Otherwise you’d see that torque=horsepower at 5250, which according to this graph would be greater than 4,000HP.

There is a caption on that chart that says it has an estimated 4,300+ft/lbs, but again the motor spins to 16,000rpm so that’s how :slight_smile:

Made this its own thread. So how would you calculate torque with a car like this?

Just need to monitor the current going to the electric motor and then look at the torque curve of the motor where it crosses 0 RPMs at the measured current.

As long as the power supply can supply the max rated starting current of the motor, then the max torque of the motor will be applied.

(That’s the basics at least; a strong EE could really go into details on this)

Ya the actual torque curve of that motor prob starts out at its max torque of 434 and stays flat through 5000 rpm before slowly fading due to lost efficiency. The dyno didn’t compensate for the 9.7:1 reduction gearing, which is why the torque number is off the chart. You could do the same thing with a gas engine by running it in 1st gear…

I want someone to write software for a 16,000 rpm tachometer so it can be displayed on the dash :slight_smile:

Apparently this type of dyno measures torque by running horsepower and wheel revolutions through an algorithm. It measures horsepower at the wheel (which, at 436 hp, wasn’t far off of Tesla’s own rating of 416 hp) and uses a stationary optical sensor interfacing with a reflector on the wheel. Every time the reflector passes the sensor, it counts one revolution. But since the Model S has shiny ten-spoke wheels (and we presume because it was taken outdoors under bright sunlight), the sensor thought that each passing spoke was one revolution of the wheel… when it was, in fact, ten times too much.