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

[krisg81]

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 the same and just changed a few numbers would that be OK with you?

Re-read what I said again.

my beef is Tesla advertising a 691HP car that outputs almost the same peak horsepower as their 422HP car, for well over $15K in additional cost when it may possibly be a software change that has a different accelerator ramping algorithm

it now seems the P85D gets to 60MPH sooner because the P85D software allows full inverter power sooner when pressing the accelerator down to the floor, and the S85 has different programming to delay the maximum power to slow down the 0-60 runs. Just like our cars can have an OTA update to speed them up and add features, it looks like acceleration numbers are being throttled via software changes and not superior performance hardware. The 691HP number seems made up as well.

if you are ok with this, so be it. Fact of the matter is P85D owners do not have a 691HP car as shown by real world testing. It's essentially a 85D with an uncrippled/lesser restricted accelerator algorithm.

To Tesla it would mean a huge profit for P85D's then. Since the car has essentially no other changes for a P85D, all they need to do is stick on a different badge and make sure to load the P85D firmware instead of the S85D firmware on the line. Pretty crazy.

 

[dennis]

Re-read what I said again.

my beef is Tesla advertising a 691HP car that outputs almost the same peak horsepower as their 422HP car, for well over $15K in additional cost when it may possibly be a software change that has a different accelerator ramping algorithm

it now seems the P85D gets to 60MPH sooner because the P85D software allows full inverter power sooner when pressing the accelerator down to the floor, and the S85 has different programming to delay the maximum power to slow down the 0-60 runs. Just like our cars can have an OTA update to speed them up and add features, it looks like acceleration numbers are being throttled via software changes and not superior performance hardware. The 691HP number seems made up as well.

if you are ok with this, so be it. Fact of the matter is P85D owners do not have a 691HP car as shown by real world testing. It's essentially a 85D with an uncrippled/lesser restricted accelerator algorithm.

If you reread with I said, you are unhappy with their implementation and the marketing HP numbers, not with the actual 1.3 sec performance delta that you paid $20K for.

Tesla has put us in a new digital world of "software defined performance". It is still early days here, as evidenced by the rapidly improving performance of the D models. Maybe the P85D is capable of 2.8 sec 0-60, but they have concerns about the impact on other components. I'm happy with what I got and am willing to give Tesla a chance to continue to improve on it. Which in my book sets them apart from every other car manufacturer.

 

[krisg81]

If you reread with I said, you are unhappy with their implementation and the marketing HP numbers, not with the actual 1.3 sec performance delta that you paid $20K for.

Tesla has put us in a new digital world of "software defined performance". It is still early days here, as evidenced by the rapidly improving performance of the D models. Maybe the P85D is capable of 2.8 sec 0-60, but they have concerns about the impact on other components. I'm happy with what I got and am willing to give Tesla a chance to continue to improve on it. Which in my book sets them apart from every other car manufacturer.

Thanks for your input and opinion Dennis.

 

[EarlyAdopter]

it now seems the P85D gets to 60MPH sooner because the P85D software allows full inverter power sooner when pressing the accelerator down to the floor, and the S85 has different programming to delay the maximum power to slow down the 0-60 runs. Just like our cars can have an OTA update to speed them up and add features, it looks like acceleration numbers are being throttled via software changes and not superior performance hardware. The 691HP number seems made up as well.

It's not just software. There is a hardware difference to allow for that current ramp, but it's not the motor.

Going back a bit to refresh everyone, the hardware difference between the P85 and the S85 was the inverter - performance models got a performance inverter in the drivetrain which allowed more current to be dumped into the motor. Not just software. Extra copper. But the motors were the same. Was that worth $10,000?

The hardware differences between the P85D and the S85D are both the inverters and the rear motor. Again, it's not just software that allows that current to ramp faster - it takes more copper and beefier components in the inverters to allow for that greater ramp up. The higher sustained peak is probably the hardware difference between the rear motors. Again, worth it?

What does BMW or Porsche charge for an extra 1.3 sec off?

 

[stopcrazypp]

The only hardware difference between the P85 and the S85 was the inverter - performance models got a performance inverter in the drivetrain which allowed more current to be dumped into the motor. Not just software. Extra copper. But the motors were the same. Was that worth $10,000?

Right. The power numbers are a bit misleading as they mix current and voltage together. In order to generate lots of power at low rpms you need a lot of current (because of lower motor voltage at low rpm and the need to generate high torque). The main difference in the P85 vs S85 was the inverter peaked at 1200 amps while the S85 peaked at 900 amps.

The power graph wasn't that different either (310kW vs 270kW, a 40kW difference):

http://www.teslamotorsclub.com/show...-Model-S/page6?p=639634&viewfull=1#post639634

 

[Danal]

Right. The power numbers are a bit misleading as they mix current and voltage together. In order to generate lots of power at low rpms you need a lot of current (because of lower motor voltage at low rpm). The main difference in the P85 vs S85 was the inverter peaked at 1200 amps while the S85 peaked at 900 amps.

Perhaps I am misreading or misunderstanding your statement. A free running AC induction motor, for a given voltage applied, will turn at a characteristic RPM called the "RPM per Volt", minus a small percentage (that is directly related to the efficiency of the motor). If mechanical load is added, the motor attempts to hold that RPM by drawing more current. Other than any sag caused by the supply being unable to keep up, the Voltage does not change.


Another way to look at the same thing: Voltage is "push" or pressure. Amps is flow. You make a motor go faster in RPM (if it can), or draw more amps (if the mechanical load constrains it) by pushing more voltage at it. Current is not something you can "push", only pressure (Volts). Current results from that push, and the load on the motor, and a few other factors. There is literally no way to lower voltage and increase current at the same time (for a given motor, and given load on that motor).

 

[AWDtsla]

Re-read what I said again.

my beef is Tesla advertising a 691HP car that outputs almost the same peak horsepower as their 422HP car, for well over $15K in additional cost when it may possibly be a software change that has a different accelerator ramping algorithm

it now seems the P85D gets to 60MPH sooner because the P85D software allows full inverter power sooner when pressing the accelerator down to the floor, and the S85 has different programming to delay the maximum power to slow down the 0-60 runs. Just like our cars can have an OTA update to speed them up and add features, it looks like acceleration numbers are being throttled via software changes and not superior performance hardware. The 691HP number seems made up as well.

if you are ok with this, so be it. Fact of the matter is P85D owners do not have a 691HP car as shown by real world testing. It's essentially a 85D with an uncrippled/lesser restricted accelerator algorithm.

To Tesla it would mean a huge profit for P85D's then. Since the car has essentially no other changes for a P85D, all they need to do is stick on a different badge and make sure to load the P85D firmware instead of the S85D firmware on the line. Pretty crazy.

That's not what's going on. First of all, horsepower is a stupid way to rate car motors, but they're advertised because everyone wants a number, and more is taken as better always. Torque is what matters, and in the case on an electric motor, torque is current. The graphs above showing power output are basically mixing two different axes, speed and torque, and then plotting them as one, which just confuses the issue. The P85D is putting down a "****-ton" more torque than the 85D. A 30% improvement in the 0-60 of a 5000lb car? That's amazing.

 

[Matias]

If you reread with I said, you are unhappy with their implementation and the marketing HP numbers, not with the actual 1.3 sec performance delta that you paid $20K for.

Tesla has put us in a new digital world of "software defined performance". It is still early days here, as evidenced by the rapidly improving performance of the D models. Maybe the P85D is capable of 2.8 sec 0-60, but they have concerns about the impact on other components. I'm happy with what I got and am willing to give Tesla a chance to continue to improve on it. Which in my book sets them apart from every other car manufacturer.

So just to make sure; in this new "software defined performance" a car maker can say, that a car has X hp even though it has not?

 

[AWDtsla]

What does BMW or Porsche charge for an extra 1.3 sec off?

M3 vs 335i, 10-15k. But the total purchase price is nearly half of that pf the P85D, which clearly makes the P85D a better deal. Porsche is just ludicrous for price increase to their top end models, it's not even worth bringing up.

 

[krisg81]

M3 vs 335i, 10-15k. But the total purchase price is nearly half of that pf the P85D, which clearly makes the P85D a better deal. Porsche is just ludicrous for price increase to their top end models, it's not even worth bringing up.

Actually, a good example of the BMW being the better deal here.

for their $10-15K performance package, they get much more than a 1 second shave off their 0-60. They are getting better wheels and tires, better and more capable braking system, better cooling system for harsh track racing conditions, better seats, better motor, better transmission, better electronic tracking and ESP tuning, better exhaust system, more aggressive body styling, better EVERYTHING. That premium is completely more understandable. The performance version of the P85D gets an apparent software change that makes the power ramp sooner for a quicker 0-60 time. No other changes.. No better braking, cooling, etc. a $2 badge change and the software engineer presses the #1 instead of the #2 on the firmware loading on the production line. For $15-20K additional.

 

[billarnett]

...P85D gets an apparent software change that makes the power ramp sooner for a quicker 0-60 time. No other changes...

?? As stated just a few posts back, The P85D gets a different rear motor and beefier inverter(s). And red brake calipers!

 

[EarlyAdopter]

The performance version of the P85D gets an apparent software change that makes the power ramp sooner for a quicker 0-60 time. No other changes.. No better braking, cooling, etc. a $2 badge change and the software engineer presses the #1 instead of the #2 on the firmware loading on the production line. For $15-20K additional.

You're mistaken. It takes more than just software to allow for a greater in-rush of current.

Please see my post above.
P85D 691HP should have an asterisk * next to it.. - Page 45

 

[Realist]

Actually, a good example of the BMW being the better deal here.

for their $10-15K performance package, they get much more than a 1 second shave off their 0-60. They are getting better wheels and tires, better and more capable braking system, better cooling system for harsh track racing conditions, better seats, better motor, better transmission, better electronic tracking and ESP tuning, better exhaust system, more aggressive body styling, better EVERYTHING. That premium is completely more understandable. The performance version of the P85D gets an apparent software change that makes the power ramp sooner for a quicker 0-60 time. No other changes.. No better braking, cooling, etc. a $2 badge change and the software engineer presses the #1 instead of the #2 on the firmware loading on the production line. For $15-20K additional.

Actually many owners of the new M3 are complaining that the car is basically a tuned 335i. It is not. However, in the old days BMW M cars had there own engine lines. That's gone. Anyway every car manufacturer charges horrendous money for software upgrade or very minor different hardware. Porsche has been doing that for years with the Cayman/Boxster. 10hp for 4000,-.

P85D has a unique dual motor setup. It's the fastest Tesla out there. If you want the very high end in the line up you always pay a Premium. You just cannot compare this car with a classic 700hp muscle car.

 

[wk057]

I don't think anyone is really saying the P85D isn't awesome... however I do have an issue of advertised specs vs. real world specs being far different.

For me with the P85D this began with the advertised efficiency at the time of my order being way better than the efficiency at delivery. It's still not as good as originally advertised, IMO, but it's about as good as my P85, so, I'm happy with it.

For power, though... guess this will be a new issue. Just ordered a PerformanceBox.

 

[Andyw2100]

For power, though... guess this will be a new issue. Just ordered a PerformanceBox.

I see new videos on the horizon...

 

[Matias]

Just ordered a PerformanceBox.

I'm a complete newbie on this, but what kind of info it will give you regarding this hp question?

PerformanceBox info page says "Perform a coast-down test to measure drag, and the PerformanceBox will calculate HP at the flywheel." But you can't do coast down, because regeneration is always on?

Apparently you get wheel hp, but not flywheel hp?

 

[Stoneymonster]

Revised the graph with better speed axis. The speed comparison is pretty useless though because of the different starting speeds.

 

[joer00]

?? As stated just a few posts back, The P85D gets a different rear motor and beefier inverter(s). And red brake calipers!

Well do all MS now have the P+ suspension ?? That was a 6500$ value included in the P which made the D just 4500 $ more expensive than the old P85+, a REAL bargain in my opinion.

The 1.3 seconds difference is the same as between the Panamera S which does 4.9 seconds and the Panamera Turbo S which is 3.6. seconds. Price difference 87.000 $
You can buy a 85D just for that price difference !

 

[krisg81]

Revised the graph with better speed axis. The speed comparison is pretty useless though because of the different starting speeds.

Thanks for this Stoney.

I am happy with the performance of the P85D (it seems some do not understand that) but just looking at this and the data from the 85D vs P85D, I just don't see how there is a 269HP delta between them. The only true difference is how quick one gets to their peak horsepower vs the other, and the peak horsepower is around 500 (85D) vs 560 (P85D).

So really, Tesla's true performance rating when advertising the car is clearly geared for only 0-60 times. I have seen no conclusive claims, only speculation meant to look like fact, that the 85D and P85D have actual hardware and mechanical power train differences and are not just detuned/tuned software tweaks.

There is a slight increase in the amount of power to both motors in the P85D, but the real difference in 0-60 performance is accelerator mapping. The firmware clearly goes to 100% faster when the accelerator is floored, and the S85D accelerator makes sure to ramp to 100% at a slower rate. Some people are claiming there is a inverter and/or motor change to make that happen, yet there is no actual proof that is occurring. Sounds like a software tune to me.

At the end of the day, the car is advertised as 691 horsepower and it simply does not output that much power. The S85D is advertised at 422HP and puts out more than advertised power. I know some people here will defend Tesla & Elon until they are blue in the face, but I think Tesla has some explaining to do here regardless of our satisfaction in the current 0-60 times.

 

[Stoneymonster]

Well, on the flip side of the coin, I would be pissed if there's a bunch of dead weight in my S85D for the larger P motor in the rear.