[updated with *] P85D 691HP should have an asterisk * next to it.. "Up to 691HP"

[AWDtsla]

Thanks Pete, this is quite interesting.
So, the max we logged for the P85D was 415 kW at 100% SoC.
The P90D is supposed to accelerate 20% faster from 0 to its max speed (10% faster 0 to 60 due to traction).
I would assume that this requires at least 20% more power from the battery to achieve.
415 x 1.2 = 498 kW...

Hope you are able to do some logging at 100% SoC to check if you can go higher than 456 kW.
There's also the possibility that the full 1500A has not yet been released.

No that's not right, you're using the wrong units. kW is power, and power is measured as energy over time. What you actually want is the total amount of energy, which you have to integrate the power output with respect to time to get. You could certainly accelerate to 155 faster with less power but more energy output over the whole run, because the Model S (much like _everything_ else) does not output a fixed power at every timeslice.

It's funny in a thread about HP we can't even seem to get down what we're talking about, forget about why it matters.

 

[Pete90D]

It's funny in a thread about HP we can't even seem to get down what we're talking about, forget about why it matters.

I haven't read the whole thread, but I may have derailed the conversation. If so, sorry about that.

 

[smac]

The car didn't wiggle around a lot, but you could feel this kind of jittery loss of power like when wheels do spin. In some ways this is concerning to have it happen at 40mph when you launched at 0 and didn't have the feeling 0-30. Flooring a powerful car at speed and spinning tires has been done, but losing traction half way through while full throttle the whole time seems crazy. It aligns with Elon saying 30-60 is where the power is higher, but it makes me wish they had put 21x10s or 21x11s on the car.

Sounds like it's software capped up to 40, and then kicks into full power, makes a lot of sense to limit the power early on rather than rely on the TC/ESP which will apply brakes in lieu of an LSD.

For sure the tires are narrow for a car of this size, let alone one with the power of yours! Sticking wider ones on though would really hurt range. Like everything in life it's about compromise

 

[AWDtsla]

I haven't read the whole thread, but I may have derailed the conversation. If so, sorry about that.

It was never on the rails anyway ;-)

 

[sorka]

There's no way the P90D is going to hit the 1/4 mile in 10.9 unless that kW output grows more. Wonder if it's really capped at 456 or it it will climb again after some speed? If you can get onto that airfield that would be cool.

 

[Pete90D]

Sounds like it's software capped up to 40, and then kicks into full power, makes a lot of sense to limit the power early on rather than rely on the TC/ESP which will apply brakes in lieu of an LSD.

For sure the tires are narrow for a car of this size, let alone one with the power of yours! Sticking wider ones on though would really hurt range. Like everything in life it's about compromise

Who needs range when the best part is the first 152 feet? J/k, range is nice too

 

[jpet]

No that's not right, you're using the wrong units. kW is power, and power is measured as energy over time. What you actually want is the total amount of energy, which you have to integrate the power output with respect to time to get. You could certainly accelerate to 155 faster with less power but more energy output over the whole run, because the Model S (much like _everything_ else) does not output a fixed power at every timeslice.

Thanks for clarifying. So the peak power of 415 kW in a P85D is possibly only available during a fraction of the run. If the P90D runs at almost the same peak power but is able to maintain peak power longer so that it outputs 20% more energy over the same distance, it should be around 20% faster?

 

[sorka]

Thanks for clarifying. So the peak power of 415 kW in a P85D is possibly only available during a fraction of the run. If the P90D runs at almost the same peak power but is able to maintain peak power longer so that it outputs 20% more energy over the same distance, it should be around 20% faster?

If you're talking 0-60, then we already know that peak power on the P85D occurs at 36 MPH and continues on well past 90 MPH where it slowly tapers off. The P90D may *not* taper off so it will be interesting to see data acquisition at higher speed.
The P90DL peaks 56 hp more but doesn't hit that peak until 48 MPH and continues mostly flat at least up to the 60 mph point. Pete doesn't show data beyond that presumably because he was only doing 0-60 runs.

 

[AWDtsla]

Thanks for clarifying. So the peak power of 415 kW in a P85D is possibly only available during a fraction of the run. If the P90D runs at almost the same peak power but is able to maintain peak power longer so that it outputs 20% more energy over the same distance, it should be around 20% faster?

Slightly more complicated than that. If it was in a vacuum it might be that easy (well except for energy increases with the square of velocity, as below), but drag makes it much more complicated. The less time you spend accelerating the less your drag losses are.

Ignoring drag, using E=.5mv^2, increasing v by 20% means increasing the energy output by 44%

 

[jpet]

Ignoring drag, using E=.5mv^2, increasing v by 20% means increasing the energy output by 44%

Ok, so from this I take that 415 kW and possibly even 456 kW peak power will not be enough to reach the advertised 20% improvement in time to get to top speed over the P85D.

 

[stopcrazypp]

From this video it takes 27 seconds to go from 161 kph (100mph) to 247kph (153 mph)
https://www.youtube.com/watch?v=19KAd7-MTrQ

0-100mph (with rollout) takes 8.6 seconds.
http://www.motortrend.com/roadtests...rt_hellcat_vs_tesla_model_s_p85d/viewall.html

So it takes roughly 35-36 seconds to reach 153mph in the P85D. 20% improvement would be 28-29 seconds.

I plugged in 247kph, 36 seconds, 2320(2239+81)kg, got 152kW.
I plugged in 247kph, 29 seconds, 2320(2239+81)kg, got 188kW.
http://www.engineeringtoolbox.com/car-acceleration-d_1309.html

That represents 24% (36kW) more power for that improvement purely for acceleration.

 

[thegruf]

do I recall correctly that Elon said it was the 60-155 mph time would improve by 20% not the 0-155 mph time

so in approximate terms from the figures above
0-60 is 3.2 secs
0-100 is 8.6secs
100-155 is 27 secs
so 60-155 is 8.6-3.2+27 = 32.4 secs

a 20% improvement on this would be appx 6.5 secs bring the 60-155 down to iro 26 seconds

... I may this this all wrong of course

 

[lklundin]

Tesla speed on long distance is about 70km/h (45 mph). This is what they got during coast to coast rally.
It is not a problem to get double that in ICE car in Germany, traffic permitting.

Traffic permitting, in Germany the 940 km from the border in the North down to Munich can be driven in just over 5 hours with a good diesel car (including one stop for fuel).

This sustained average speed of just over 180km/h has got to be the worst case public-road scenario for Tesla to compare with.

Also, on the same autobahn I managed to get that pesky, yellow line delimiter in an early P85+ already when the battery was at about 75%. I am trying to attach a screen shot of that.


View attachment 92965

 

[AWDtsla]

View attachment 90823

The 85D crowd got a massive horsepower boost to 376 KW or 497 hp yet the spec only says 417. And on top of that, the 39 KW (52 hp) difference between the 85D and P85D is only that if the P85D is charged to 100%. As the SOCs of both decrease, they eventually converge. Most of us are cutting the P85D a break in these discussions because we've been talking in terms that are only true at 100% SOC rather than the typical daily driving range.

Did anyone get a similar plot for the 85D?

 

[vgrinshpun]

Tesla added the 1 foot rollout disclaimer to their main U.S. order page:

 

[Sad]

Interesting, base option only? Could that mean that Ludicrous mode would improve 0-60 acceleration by 0.6 seconds (i.e. 0.3 + 0.3) ???

By the way, I still don't understand why they wouldn't use the same methodology for all models, it would (cosmetically) improve the performance of all other models to even better figure. Or maybe I do understand, it's just the way to maintain a big enough gap to justify the 20K price difference.

 

[Matias]

Tesla added the 1 foot rollout disclaimer to their main U.S. order page:

good. But strange, that they haven't (yet?) put that disclaimer to other sites.

 

[darthy001]

Wow, something is actually happening! Guess all the "whining" wasnt for nothing after all

 

[loco]

Traffic permitting, in Germany the 940 km from the border in the North down to Munich can be driven in just over 5 hours with a good diesel car (including one stop for fuel).

This sustained average speed of just over 180km/h has got to be the worst case public-road scenario for Tesla to compare with.

Also, on the same autobahn I managed to get that pesky, yellow line delimiter in an early P85+ already when the battery was at about 75%. I am trying to attach a screen shot of that.


View attachment 92965

Did you drive it in the Model S? I'm guessing 9 hours driving + 4 hourly stops.

- - - Updated - - -

Tesla added the 1 foot rollout disclaimer to their main U.S. order page:

This is great.

Revealing horsepower output of P85D would be even better.

 

[Andyw2100]

Tesla added the 1 foot rollout disclaimer to their main U.S. order page:

That's definitely a step in the right direction.