Submitted by didier borremans on Mon, 2012-08-27 10:24

How come, if i floor my roadster in performance mode from standstill, i only have 237hp in stead of the expected 300hp?
Anyone?

ggr |
27 augustus 2012

You have full *torque* from 0 rpm. But power depends on the rpm, too. Technically, at the moment you floor it, you have 0 power, because you're not moving yet. Maximum power occurs at the rpm point where the torque starts to drop off, around 55mph IIRC.

Brian H |
28 augustus 2012

Yep, accel from 0 requires infinite power.
;)

didier borremans |
29 augustus 2012

Of course, i understand ;-)
However, i went up from standstill up to >80mph and still, the max hp reached was 260hp.
Under which conditions would it go up to 300hp?

didier borremans |
29 augustus 2012

actually, the max reached was 270hp (not 260hp), but still ...

Timo |
31 augustus 2012

How do you measure HP? Is it some display on Roadster?

DHrivnak |
31 augustus 2012

I have a 1.5 Roadster and it's HP peak is 241, I have seen as much as 245 but the "rating" is only 241. And yes the VDS has a screen that shows you the HP, torque and g forces. It is kind of cool.

Timo |
3 september 2012

Wild guess: 300HP is actual motor rating, IE. how much electrical power it drains from the batteries when you floor it independent of motor RPM (conversion of watts to HP), and HP what you actually get is measured by combination of RPM and torque (actual HP definition). You never reach the rated power because motor torque in Roadster starts to drop before it reaches RPM that equals 300HP.

Aidenn |
15 november 2012

The exact definition of one hp is 33,000 lb.ft./minute. Put another way, if you were to lift 33,000 pounds one foot over a period of one minute, you would have been working at the rate of one horsepower. In this case, you'd have expended one horsepower-minute of energy.

ggr| 27 augustus 2012You have full *torque* from 0 rpm. But power depends on the rpm, too. Technically, at the moment you floor it, you have 0 power, because you're not moving yet. Maximum power occurs at the rpm point where the torque starts to drop off, around 55mph IIRC.

Brian H| 28 augustus 2012Yep, accel from 0 requires infinite power.

;)

didier borremans| 29 augustus 2012Of course, i understand ;-)

However, i went up from standstill up to >80mph and still, the max hp reached was 260hp.

Under which conditions would it go up to 300hp?

didier borremans| 29 augustus 2012actually, the max reached was 270hp (not 260hp), but still ...

Timo| 31 augustus 2012How do you measure HP? Is it some display on Roadster?

DHrivnak| 31 augustus 2012I have a 1.5 Roadster and it's HP peak is 241, I have seen as much as 245 but the "rating" is only 241. And yes the VDS has a screen that shows you the HP, torque and g forces. It is kind of cool.

Timo| 3 september 2012Wild guess: 300HP is actual motor rating, IE. how much electrical power it drains from the batteries when you floor it independent of motor RPM (conversion of watts to HP), and HP what you actually get is measured by combination of RPM and torque (actual HP definition). You never reach the rated power because motor torque in Roadster starts to drop before it reaches RPM that equals 300HP.

Aidenn| 15 november 2012The exact definition of one hp is 33,000 lb.ft./minute. Put another way, if you were to lift 33,000 pounds one foot over a period of one minute, you would have been working at the rate of one horsepower. In this case, you'd have expended one horsepower-minute of energy.