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75D upgrade to P100D

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This might be a stupid question but when we talk about speed difference and not just battery capacity does a 75D have software limitations that prevent it from having a 0 to 60 like a P100D? Or are there physical differences that support the extra power to the wheels.
 
Compared to the P100D, the 75D has the following that limit its acceleration:
  • Battery is 14 modules instead of 16, which means 350V nominal battery voltage instead of 400V.
  • Lower capacity battery (kWh) means that less current (A) can be drawn from the battery without cell damage. 75D max current is around 950A. P100D max current is around 1600A.
  • 75D's motors are both the small motors capable of ~ 185 kW each. P100D's rear motor is the large motor, capable of ~ 360 kW (front motor is the same as the 75D, ~ 185 kW).
 
Tesla used to list the horsepower rating of the various motors in the specs on their website, but apparently do not do so any longer. (Or I can no longer find them.)
Back when they did, they also distinguished between the horsepower of the motors themselves and the maximum power that could be delivered to the motors by the battery (which Tesla called the "Battery Limited Maximum Motor Shaft Power," or BLMMSP.

I captured some of those specifications when they were available in late 2015, as follows:

The 75D had motor sizes of 259 HP both front and rear, with a BLMMSP of 328 HP and torque of 387 lb-ft. That resulted in published 0-60 time of 5.2 seconds.
The 90D and 100D had motors of the same size as the 75D, with a BLMMSP of 417 HP and torque of 485 lb-ft, 0-60 in 4.2 seconds.
The performance models had a larger rear motor, with 259 HP in the front and 503 HP in the rear, and a BLMMSP of 463 for the P85D and P90D as of 11/1/2015. With Ludicrous, that became 532 HP. Torque was 713 on all three of the P models.
So far as I know, Tesla did not ever publish BLMMSP values for the P100D, or if they did I missed them.

The 0-60 times for the performance models were then listed as 3.1 for the P85D, 2.8 for the P90D, and 2.5 for the P100D with Ludicrous.
These data are all for Model S.

(If these figures are still published somewhere and I have missed where they are, please provide a link.)

So, bottom line, there are indeed physical differences in the motors for the performance models, and in addition the larger \batteries can deliver more power to the motors so the effective horsepower is higher. (Ludicrous mode also involves some different fusing for the battery, with unique software for the fuse itself.)
 
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Simple way to look at it is:
  • 75D is limited by power that the battery can deliver
  • Add bigger battery that can deliver power power to the same motors, that's 90D/100D
  • Add a more powerful motor on the back and upgrade battery connectors so more peak power can be delivered without damage - that's P100D.
Or:
  • P100D = 100D + bigger motor + upgraded battery connectors
  • 100D = 75D + bigger, more powerful battery
To answer OP's question directly, yes, there are software limitations that limit power on the 75D, but those are to keep the battery from damaging itself, even catching on fire (as I did once in the past on my RC helicopter by accidentally ignoring the prescribed battery power limit and programming the motor controller for more power - I did get more power, followed by an immense cloud of smoke, helicopter crash and melted parts).
 
I wonder what is the output voltage of a supercharger?
My understanding is that the supercharger voltage must be higher than the voltage of the battery pack or it can't charge.

Supercharger output voltage is variable, and is controlled at the supercharger cabinet. The voltage typically will be 5-15 volts above the battery open-circuit voltage for most of the charge. Towards the end, the difference in voltage gets smaller as the charge rate ramps down.

A 350V nominal battery pack (installed in 40/60/70/75 cars) will be around 300V when nearly empty. The supercharger will start ramping up the current and you'll see the voltage on the charging display come up (along with current and power). 85/90/100 cars have the 400V nominal battery packs, and the supercharger does the same thing, but just starts at a higher voltage.
 
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Reactions: ricebucket
Since power (measured in watts) is Amps x Volts, the car will increase the amps when the battery is low because, when low, the voltage is less so increasing the amps keeps the power output about the same. Otherwise, your power output would diminish at lower SOCs. The P models suffer lower overall power at low SOCs, but not so much on the non-P models.
 
I went with P100DL and never looked back. But for maximum performance, you need to heat up the battery, I saw my message says over 50 minutes, what a bummer.

I used SPORT in the first week, and switched to LUDICROUS in the second week, noticed the difference, but after a few days, I get used to it. So my conclusion is that there is probably no need to upgrade just for the incremental gain which you will likely ask for more anyway, like a drug. Keep your 75D till some major model updates.
 
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So my conclusion is that there is probably no need to upgrade just for the incremental gain which you will likely ask for more anyway, like a drug. Keep your 75D till some major model updates.

That's interesting. I bought my 75D in July and now I'm thinking about upgrading to 100D or maybe P100D mainly for performance (I'm not a car person but that acceleration is like you said a drug) but also technology, I basically missed AP2.0 by couple of weeks, and finally range. Seeing you drive a P100DL and you get used to it, I'm not too sure about it anymore especially with that price tag.

Do you think the upgrade to 100D is worth it to get the better of all 3 or should I just stop worrying and enjoy my amazing car
 
Compared to the P100D, the 75D has the following that limit its acceleration:
  • Battery is 14 modules instead of 16, which means 350V nominal battery voltage instead of 400V.
  • Lower capacity battery (kWh) means that less current (A) can be drawn from the battery without cell damage. 75D max current is around 950A. P100D max current is around 1600A.
Hmm, but each of these 14 modules are similar in capacity to the 16 modules in the 90 battery, which can draw 1600 amps. I think there is a software limit at 950A for 75 batt and that it too can draw 1600 A with the Ludi fuse and thus get over 500kW. Agreed though that the drive units couldn't fully make use of it.
 
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This might be a stupid question but when we talk about speed difference and not just battery capacity does a 75D have software limitations that prevent it from having a 0 to 60 like a P100D? Or are there physical differences that support the extra power to the wheels.

At the recent shareholders meeting Elon stated that battery upgrades are done (?), but that it is not possible to upgrade from the smallest to the biggest battery (presumably from 75 kWh to 100kWh). He also stated that this is also not recommendable for newer cars and one should rather buy a new car (presumably =extremely expensive). The way he referred to it seems that there are technical limitations for that and my guess is that it primarily has to do with weight issues due to the heavier batteries (and less so with voltage and current differences)
 
This might be a stupid question but when we talk about speed difference and not just battery capacity does a 75D have software limitations that prevent it from having a 0 to 60 like a P100D? Or are there physical differences that support the extra power to the wheels.

Batteries do not push power. They allow power to be drawn from them. A 75 upgraded to a 100 is "probably" possible and wouldn't change acceleration much other than higher capacity could allow lower internal resistance and thus less power loss during hardest acceleration of the 75's electric motors. Probably would be a $15k to 20k process.

Someone (D. Nolan) wrote in Green Car Reports a while back about upgrading his 60 to an 85. Couple years ago. Was a battery swap and cash swap.
 
Hmm, but each of these 14 modules are similar in capacity to the 16 modules in the 90 battery, which can draw 1600 amps. I think there is a software limit at 950A for 75 batt and that it too can draw 1600 A with the Ludi fuse and thus get over 500kW. Agreed though that the drive units couldn't fully make use of it.
It does sound as if the 75s are possibly artificially limited to differentiate with the 90/100 (non-P).
 
Hmm, but each of these 14 modules are similar in capacity to the 16 modules in the 90 battery, which can draw 1600 amps. I think there is a software limit at 950A for 75 batt and that it too can draw 1600 A with the Ludi fuse and thus get over 500kW. Agreed though that the drive units couldn't fully make use of it.

With 14 modules the maximum current draw is going to be reduced too. The Ludicrous version does have a special fuse that allows maximum current flow from the battery for a short sprint. With the pair of smaller motors on the 75D and the 90D, there is probably a limit to the current the pair of motors can take. The P85D/P90D/P100D has the much larger rear motor that can probably handle more current than the small motors can.

This chart gives a lot of the data for most versions of the car:
Tesla Model S - Wikipedia

I'm perfectly happy with the acceleration of my 90D. When passing I hit 80 without trying and don't even push the accelerator anywhere near the floor. If I was interested in drag racing I might have some interest in a P100DL, but the situations where you can really use it outside of a track environment is very rare. It just isn't worth the steep premium for something few people are really going to take full advantage of. I'd also rather have the better range you get with the non-performance big battery car.