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

[thegruf]

^ hey- soon as you can please kris

I'm still dithering whether to order S85D or P85D and this data could really help.
As has been said above - something doesnt add up here.

If I hold off much longer they'll probably change the damn range again!

 

[krisg81]

^ hey- soon as you can please kris

I'm still dithering whether to order S85D or P85D and this data could really help.
As has been said above - something doesnt add up here.

If I hold off much longer they'll probably change the damn range again!

I am going to try and get that data log this weekend if I can find the time to set it all up!

also, don't make your decision yet. There is still the off chance there is a performance enhancing update for the P85D, and not just a battery/hardware update to get to 2.8s 0-60.

one thing that stood out was Elon's Twitter exchange with some celebrity no one cares about. He said that maybe the Model S "could" get there (I reference to 2.8s 0-60). What really caught my attention was he said "Maybe it would be a good warm up act for April 30th event". This tells me he may want to make a big deal about a firmware update that enhances the performance to the P85D Before the announcement of what I think will be a home battery system. Hopefully it's not a new model that eliminates the 85kw models! But I'm holding off thinking this whole debacle of underrated power may be solved with a firmware update.. One can hope at least!

 

[gordo]

There's also this:
P85D to get 768PS??

768 PS is roughly 757 HP.

 

[thegruf]

There's also this:
P85D to get 768PS??

768 PS is roughly 757 HP.

I spotted that too.
What a rush of updates.

My "today" purchase has become a "this month" purchase.

What I really want to see is torque curves, but the data logs are probably the nearest we will get and at least they are comparable between models and sw releases.

 

[loco]

The cherry on top is the P85D that states 691 Motor HP ... but NO total HP like the other models. Well, what is it Tesla?

That is the question. My best guess for P85D is 375 kW/ 500 HP. And this is available only up to about 100mph and only with cold motors. 375 is what the gauge shows. I know it's hard to accept

Did some driving around with a 373 kW c-class wagon and boy does it pull away from the Tesla at high speed. It's 600 kg lighter though.

 

[falconeer]

No it's not, it just means as your approach 0 velocity your torque approaches infinity and as you approach 60 your torque approaches zero, which means your acceleration force at 60 is also 0, not 0.882g. Of course infinite torque is impossible so no car will ever achieve that, and no one wants to stop accelerating at 60. But an electric motor can get close. AC induction motors are also known for super high torque (and therefore super high current draw) when held stationary, which is why many come with start capacitors.

I'm not sure if you read/understood my comment so I'll clarify:

Your original comment was about peak power vs. acceleration performance. You calculated that 350hp is necessary to accelerate an object from 0-60 in 3.1s.

Again, that is right as average, but is a useless number because it is not possible to actually put down that much power early on in a road car. This limitation has nothing to do with electric motors, it has to do with available grip (maximum 1.2-1.3g ideally).

For example, at 10mph, 350hp would result in: P=m*a*v => a=P/(m*v) = 262.5kW/(2300kg*4.47m/s) =2.6g of acceleration! This acceleration would be double the maximum grip and therefore impossible for a road car. However if you were going at 20mph, then at 350hp the acceleration is only 1.3g (at the limit). The same power at a higher speed results in less acceleration. The opposite is true as well: at half the speed, the same power would get you double the acceleration (except, in the real world, you can't actually accelerate faster than 1.3g in a road car). This fact has nothing to do with air resistance or electric vs. ICE, just basic physics.

If I'm not convincing you take look at my previous comments on pg37. I gave you a link to actual data from a DragTimes 0-60 test where you can see the speed and acceleration vs. time (you can find the maximum whp from that chart using P=m*a*v!). I'll save you time, but doing the math at around ~55mph, acceleration is 0.65g, and using a mass of 2300kg you get a peak of 360kW (480whp) or around 550hp from the battery assuming 13% loss.

 

[jerjozwik]

For example, at 10mph, 350hp would result in: P=m*a*v => a=P/(m*v) = 262.5kW/(2300kg*4.47m/s) =2.6g of acceleration! This acceleration would be double the maximum grip and therefore impossible for a road car.

i hear the april 30th update will take care of that....

 

[krisg81]

Ok - some data here.

I ran the TeslaMS API that Stoney was using, but could not get the visual graph stuff to work unfortunately. However, I did get a log of the data. Here is the data straight from the car.. Stoney, any way to overlay this with your 85D (with latest Sport mode) data?

Keep in mind this test was done with an 80-81% SOC... BOLDED was when I went did a 0-60 run, but I don't think it captured data all the way to 60. Seems the inverter kW's look low? This was done in Insane mode as well:

timestamp,speed,soc,power


1428880973985,8,80,0
1428880974235,8,80,-2
1428880974735,8,80,-0
1428880975235,8,80,3
1428880975486,8,80,5
1428880975735,9,80,7
1428880975985,9,80,9
1428880976235,10,80,16
1428880976486,11,80,22
1428880976735,12,80,34
1428880976985,14,80,41
1428880977236,15,80,52
1428880977485,17,80,79
1428880977735,21,80,185
1428880977985,25,80,291
1428880978235,32,80,377
1428880978485,36,80,387
1428880978735,41,80,372
1428880978985,43,80,217
1428880979235,44,80,39
1428880979485,44,80,15
1428880979735,44,80,2
1428880979986,45,80,1
1428880980235,45,80,-11
1428880980485,45,80,-20
1428880980736,45,80,-43
1428880980985,44,80,-54
1428880981235,44,80,-58
1428880981485,43,80,-58
1428880981735,43,81,-57
1428880981985,42,81,-42
1428880982235,42,81,-13
1428880982485,42,81,-11
1428880982735,42,81,-20
1428880982985,42,81,-38
1428880983236,41,81,-51
1428880983485,41,81,-37
1428880983735,41,81,-13

 

[Stoneymonster]

Ok - some data here.

I ran the TeslaMS API that Stoney was using, but could not get the visual graph stuff to work unfortunately. However, I did get a log of the data. Here is the data straight from the car.. Stoney, any way to overlay this with your 85D (with latest Sport mode) data?

Keep in mind this test was done with an 80-81% SOC... BOLDED was when I went did a 0-60 run, but I don't think it captured data all the way to 60. Seems the inverter kW's look low? This was done in Insane mode as well:

timestamp,speed,soc,power


1428880973985,8,80,0
1428880974235,8,80,-2
1428880974735,8,80,-0
1428880975235,8,80,3
1428880975486,8,80,5
1428880975735,9,80,7
1428880975985,9,80,9
1428880976235,10,80,16
1428880976486,11,80,22
1428880976735,12,80,34
1428880976985,14,80,41
1428880977236,15,80,52
1428880977485,17,80,79
1428880977735,21,80,185
1428880977985,25,80,291
1428880978235,32,80,377
1428880978485,36,80,387
1428880978735,41,80,372
1428880978985,43,80,217
1428880979235,44,80,39
1428880979485,44,80,15
1428880979735,44,80,2
1428880979986,45,80,1
1428880980235,45,80,-11
1428880980485,45,80,-20
1428880980736,45,80,-43
1428880980985,44,80,-54
1428880981235,44,80,-58
1428880981485,43,80,-58
1428880981735,43,81,-57
1428880981985,42,81,-42
1428880982235,42,81,-13
1428880982485,42,81,-11
1428880982735,42,81,-20
1428880982985,42,81,-38
1428880983236,41,81,-51
1428880983485,41,81,-37
1428880983735,41,81,-13

Something's weird. According to this, you lifted off at 36mph?

 

[krisg81]

Something's weird. According to this, you lifted off at 36mph?

Yeah, that does seem weird. I am going to charge the car more right now and do another log.. strange...

 

[krisg81]

OK- I did a better run, this time getting up to 85MPH+, after charging to 90% SoC for close to optimal inverter power. Here are the results, start to end of run in BOLD - seems max inverter power is only 411kW when Stoney saw 371kW in the latest update for the S85D:

timestamp,speed,soc,power


1428884440820,6,90,15
1428884441069,6,90,8
1428884441319,6,90,7
1428884441569,6,90,8
1428884441819,7,90,9
1428884442319,8,90,9
1428884443069,9,90,10
1428884443819,10,90,10
1428884444319,11,90,37
1428884444569,14,90,195
1428884444819,20,90,265
1428884445069,27,90,328
1428884445319,31,90,372
1428884445569,35,90,405
1428884445819,40,90,409
1428884446069,43,90,408
1428884446319,48,90,411
1428884446569,51,90,410
1428884446819,54,90,410
1428884447068,57,90,408
1428884447319,60,90,408
1428884447569,63,90,407
1428884447819,66,90,407
1428884448069,68,90,405
1428884448319,71,90,405
1428884448569,73,90,404
1428884448819,75,90,405
1428884449069,77,90,404
1428884449319,79,90,404
1428884449569,82,90,403
1428884449819,83,90,401
1428884450069,86,90,374
1428884450319,86,90,190
1428884450569,86,90,47
1428884450819,85,90,-47
1428884451069,84,90,-68
1428884451319,83,90,-73
1428884451569,82,90,-73
1428884451819,80,90,-73
1428884452069,80,90,-72
1428884452319,78,90,-72
1428884452569,77,90,-71
1428884452820,76,90,-71
1428884453069,74,90,-71
1428884453319,74,90,-70
1428884453569,73,89,-70
1428884453819,72,89,-70
1428884454069,71,89,-69
1428884454319,70,89,-69
1428884454569,69,89,-69
1428884455069,68,89,-69
1428884455319,67,89,-68
1428884455569,66,89,-69
1428884455821,66,89,-68
1428884456069,65,89,-68
1428884456319,64,89,-68
1428884456819,63,89,-68
1428884457319,62,89,-68
1428884457569,61,89,-68
1428884457820,60,89,-67
1428884458069,59,89,-67
1428884458571,58,89,-67
1428884458819,57,89,-66
1428884459069,56,89,-66
1428884459319,56,89,-65
1428884459569,55,89,-65
1428884459819,54,89,-58
1428884460069,54,89,-47
1428884460319,54,89,-42
1428884460569,53,89,-36
1428884460819,53,89,-34
1428884461069,52,89,-23
1428884461319,52,89,-11
1428884461569,52,89,-5
1428884461819,52,89,-6
1428884462069,52,89,-14
1428884462319,52,89,-19
1428884462569,52,89,-26
1428884462819,51,89,-27
1428884463069,51,89,-28
1428884463319,50,89,-27
1428884463569,50,89,-28
1428884463819,50,89,-30
1428884464069,50,89,-33
1428884464322,49,89,-34
1428884464569,49,89,-26
1428884464819,48,89,-15
1428884465069,48,89,-5
1428884465319,48,89,1


NOTE that I did a PocketDyno+ app run on my iPhone 6+ with this run too. Those stats (keep in mind it is not as accurate as a VBOX):

Max Accel: 1.02 g's
Max Power: 438whp (326kw)
60': 1.80

0-10mph: 0.33sec
0-20mph: 0.80sec
0-30mph: 1.25sec
0-40mph: 1.76sec
0-50mph: 2.36sec
0-60mph: 3.08sec

 

[Stoneymonster]

Interesting data. Not sure how I can present this side-by-side with the 85D data without possibly distorting something. Maybe I can extract my raw data from the database and plot both in excel.

 

[AWDtsla]

OK- I did a better run, this time getting up to 85MPH+, after charging to 90% SoC for close to optimal inverter power. Here are the results, start to end of run in BOLD - seems max inverter power is only 411kW when Stoney saw 371kW in the latest update for the S85D:

Which wheels/tires do you have? Need this to calculate your wheel torque.

 

[krisg81]

Which wheels/tires do you have? Need this to calculate your wheel torque.

I have 21" staggered wheels

 

[falconeer]

Question to you and Stoneymonster: do the Dynopocket app results include 1-ft rollout? I think that it should be turned off if that is the case.

 

[AWDtsla]

I have 21" staggered wheels

Just based this on 720 revs/mile, and 9.73:1 drive ratio. In ft-lbs.

time mph kW Wheel torque Motor torque
1428884440820 6 90 15 1467 151
1428884441069 6 90 8 783 80
1428884441319 6 90 7 685 70
1428884441569 6 90 8 783 80
1428884441819 7 90 9 755 78
1428884442319 8 90 9 660 68
1428884443069 9 90 10 652 67
1428884443819 10 90 10 587 60
1428884444319 11 90 37 1974 203
1428884444569 14 90 195 8176 840
1428884444819 20 90 265 7778 799
1428884445069 27 90 328 7131 733
1428884445319 31 90 372 7044 724
1428884445569 35 90 405 6792 698
1428884445819 40 90 409 6002 617
1428884446069 43 90 408 5570 572
1428884446319 48 90 411 5026 517
1428884446569 51 90 410 4719 485
1428884446819 54 90 410 4457 458
1428884447068 57 90 408 4202 432
1428884447319 60 90 408 3992 410
1428884447569 63 90 407 3792 390
1428884447819 66 90 407 3620 372
1428884448069 68 90 405 3496 359
1428884448319 71 90 405 3348 344
1428884448569 73 90 404 3249 334
1428884448819 75 90 405 3170 326
1428884449069 77 90 404 3080 317
1428884449319 79 90 404 3002 309
1428884449569 82 90 403 2885 296
1428884449819 83 90 401 2836 291
1428884450069 86 90 374 2553 262
1428884450319 86 90 190 1297 133
1428884450569 86 90 47 321 33
1428884450819 85 90 -47 -325 -33
1428884451069 84 90 -68 -475 -49

 

[Stoneymonster]

Here's a quick and dirty overlay. I aligned them by when it looked like the power was starting to be applied. I did my run from a stop. Kris, it looks like you were already rolling at 10mph, so take the speed comparison with a grain of salt. I don't know how to have different y-axes for data in excel, so the speed looks compressed.

The integral of the P85D power is obviously >> than the 85D, even though the peak power is only about 45 kW more.

The x-axis is time in some units I haven't figured out from the REST data, and labelled incorrectly, so you can do a qualitative comparison. (is it in ms?)

 

[Danal]

I don't know how to have different y-axes for data in excel, so the speed looks compressed.

The x-axis is time in some units I haven't figured out from the REST data, and labelled incorrectly, so you can do a qualitative comparison. (is it in ms?)

Right click on the line itself ("data series") and then assign it to the secondary axis.

Timestamp is UNIX timestamp /1000. Search for any of the "Excel Unix Timestamp" formulas and throw and extra times or divide by 1000 in there, format the cell as date/time, and Viola!

 

[krisg81]

Question to you and Stoneymonster: do the Dynopocket app results include 1-ft rollout? I think that it should be turned off if that is the case.

no they do not include 1ft rollout. When I did the run I was dead stopped.

- - - Updated - - -

Here's a quick and dirty overlay. I aligned them by when it looked like the power was starting to be applied. I did my run from a stop. Kris, it looks like you were already rolling at 10mph, so take the speed comparison with a grain of salt. I don't know how to have different y-axes for data in excel, so the speed looks compressed.

The integral of the P85D power is obviously >> than the 85D, even though the peak power is only about 45 kW more.

The x-axis is time in some units I haven't figured out from the REST data, and labelled incorrectly, so you can do a qualitative comparison. (is it in ms?)

View attachment 77826

excellent. I think what we are seeing here is a potential marketing gimmick by Tesla. They state the horsepower rating of the P85D as 691HP, and the S85D as 422HP- a massive difference--- yet, clearly there is only a small HP difference. Also, my SOC was at 90% vs your 80% which would close that gap even more.

clearly, the only difference is the ramping of inverter earlier on to increase the 0-60MPH times, and when that curve diminishes the 85D is essentially performing the same as the P85D.

now, if both the 85D and P85D are running very similar peak kW draws to both motors- what is causing the quicker acceleration? Are we P85D owners simply paying for a software tweak that ramps inverter power sooner for 0-60 bragging rights or is there legitimately better more powerful hardware installed on the car?

i feel he 85D and P85D essentially share the same power train but firmware limits the acceleration- just like the recent 85D software opened up an entirely different mode.

im not happy about paying a huge premium with the false pretenses this is a 691HP car when their 85D puts out very similar horsepower. The trick here is that when flooring the accelerator the throttle takes longer to go 100% on the 85D then the P85D. There is definitely something that needs to be addressed the way Tesla is hyping horsepower numbers here.

i am really impressed by the torque output though. I'm not going to lie I am very happy with the 0-60 times, I just think there is more to be had and I want all power that was sold to me- all 691HP because the 85D guys are getting their full advertised power and then some!

85D = marketed at 422HP, puts out closer to 500HP peak
P85D = marketed at 691HP puts out close to 560HP peak

an actual difference of only 60HP or so in "real world horsepower" yet marketed as a 275HP difference to justify a much steeper price tag.

only difference in 0-60 times is how quick the inverter outputs maximum kW to the motors

something is wrong with this picture.

 

[dennis]

I'm not going to lie I am very happy with the 0-60 times, I just think there is more to be had and I want all power that was sold to me- all 691HP because the 85D guys are getting their full advertised power and then some!

85D = marketed at 422HP, puts out closer to 500HP peak
P85D = marketed at 691HP puts out close to 560HP peak

an actual difference of only 60HP or so in "real world horsepower" yet marketed as a 275HP difference to justify a much steeper price tag.

only difference in 0-60 times is how quick the inverter outputs maximum kW to the motors

something is wrong with this picture.

Let me make sure I understand this. P85D does 0-60 in 3.1 sec., while 85D takes 4.4 sec. So P85D owners are getting an actual difference of 1.3 sec in 0-60 times for the $20K delta they paid over the 85D, and your beef is with Tesla's implementation? If they left the actual performance and cost differential the same and just changed a few marketing numbers would that make it OK with you?

Personally I'm very happy that my "691 HP" 5000 lb. family sedan is now faster 0-60 than my 616 HP, 3200 lb. McLaren 12C "supercar" which cost twice as much.