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P85D motor hp controversy starts also to show in U.S. media

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Model Combined
Output (hp)
Front Motor Output (hp) Front Motor Rev (rpm) Rear Motor Output (hp) Rear Motor Output (rpm) Vehicle Speed (km/h)
P85D691





Still looking for the answers. Will these insist on 691hp being correct fill in the blanks above please?

By the way, dyno result from DragTimes shows 413hp max.
 
Every time I say GROSS, you try to derail my point by saying GROSS means different intakes and exhausts and no accessories so they can measure the maximum GROSS ICE power. When I say gross, I mean power measured before subtracting for things that could reduce power. In the case of an ICE, it's what they're attaching or not attaching to the engine. In the case of the Tesla, it's power as far upstream as you can get before conversion losses or electric accessories reduce power.
The core disagreement we have is this part. You see GROSS as taking off power robbing things. I see GROSS as a specification that allows anything other than the item under test (the engine in this case) to be non-stock.

I see no difference between using a non-stock intake and exhaust and settings (in regards to ignition timing, carburetor/fuel injection) and Tesla testing with a power supply vs the stock battery. You can throw off the point about accessories if you want, just to clarify the argument. In both cases, to achieve the advertised numbers in the car itself (if you can take a magical power probe the engine/motor shaft) you would need to have equipment and settings that is not present in the car as sold. In the ICE case, besides from changing the intake and exhaust parts, the car would have worse fuel economy and be illegal to drive on the road because of noise and emissions requirements, whereas for the Tesla it'll be an updated battery pack.

If you want to use analogies:
In the ICE case, the intake/ignition timing/carburetor/fuel injection restrict the amount of air/fuel you can take in and the exhaust causes back-pressure which is additional resistance that the engine has to work against. In the electric motor case, the battery's fuses and cell chemistry limit the amount of current you can draw, and the internal resistance of the battery reduces the amount of DC voltage seen by the inverter and ultimately the AC voltage at the motor. I don't really see a whole lot of difference between the two.

And in practical terms, the difference in power is practically the same. GROSS vs NET in the ICE case according to the article I linked can have a 25% difference, which is roughly the same as with the P85D.
 
The core disagreement we have is this part. You see GROSS as taking off power robbing things. I see GROSS as a specification that allows anything other than the item under test (the engine in this case) to be non-stock.

I see no difference between using a non-stock intake and exhaust and settings (in regards to ignition timing, carburetor/fuel injection) and Tesla testing with a power supply vs the stock battery. You can throw off the point about accessories if you want, just to clarify the argument. In both cases, to achieve the advertised numbers in the car itself (if you can take a magical power probe the engine/motor shaft) you would need to have equipment and settings that is not present in the car as sold. In the ICE case, besides from changing the intake and exhaust parts, the car would have worse fuel economy and be illegal to drive on the road because of noise and emissions requirements, whereas for the Tesla it'll be an updated battery pack.

If you want to use analogies:
In the ICE case, the intake/ignition timing/carburetor/fuel injection restrict the amount of air/fuel you can take in and the exhaust causes back-pressure which is additional resistance that the engine has to work against. In the electric motor case, the battery's fuses and cell chemistry limit the amount of current you can draw, and the internal resistance of the battery reduces the amount of DC voltage seen by the inverter and ultimately the AC voltage at the motor. I don't really see a whole lot of difference between the two.

And in practical terms, the difference in power is practically the same. GROSS vs NET in the ICE case according to the article I linked can have a 25% difference, which is roughly the same as with the P85D.

My definition of GROSS when applied to both ICE and EV is that both are getting as much fuel as the engine or motor can take before any power robbing attachments and accessories are applied to arrive at NET. My bigger point is that I'm willing to accept something from Tesla less rigorous than NET even though I shouldn't. I guess i'm just a push over and easily satisfied :)

If P85D's battery output 525KW, I can guarantee most of the folks here would not be so upset about being intentionally lied. You might even see me throwing in discounts like "yea, but Tesla's AWD power train loss is less than typical ICE AWD losses, so give them a break". But the reality is they threw out a number that is so *far* from reality that no amount of handicaps or discounts can make up for it.
 
I still don't get why a 70D is rated way less than the sum of its motors but a P85D isn't.

but nobody wants to answer that and the only person I've seen acknowledge the question suggested we shouldn't confuse matters. There's no confusion in my mind, it's exactly the same logic, or should be.


Apparently the argument is that the 70D isn't in Tesla's performance line up, so therefore Tesla are "allowed" to do this.


Saying that I too don't understand the logic in that argument. Though there have been some comments about some US manufacturers taking this approach, which is even more confusing, as JB himself said they were using a European measurement standard, and AFAIK, the likes of BMW don't switch reporting metrics between M and non-M cars.

I'm still very confused!
 
Still won't do 10.9. And I'm betting it still won't til they get lighter batteries and a 110k pack.
and that's the only way as I've said all along that it will it be able to achieve 300 miles.

and believe me when the 3 or E come out and it does likely get 220 miles on a charge for $40k, there will need to be a major price drop in the model S or a major increase in mileage and speed to justify 40,000 versus 140,000
 
No there isn't.

If we believe your interpretation of R85, then there is no standard for rating vehicle horsepower for EVs.

If we believe your interpretation, that standard specifies motor capacity which is not achievable in the shipping vehicle and is not a substitute for declaring vehicle horsepower.

Don't make me copy and paste my bullet list again :)


Here are few details that I think worth noting:

The standard does not "specify motor capacity" it establishes procedure for rating of electric drivetrains.

My interpretation is the same as JB Straubel's and Tesla Motors Engineering, but arrived at independently, prior to JB Straubel's Blog post. The interesting part is that some members active on the threads relating to "missing horsepower" were aware of this regulation for quite some time, but, apart from Stopcrazypp, they did not care to carefully read through it, apparently because there was nothing there to support their views.

Your bullet list, aside from the first bullet that I addressed, has nothing to do with the Standard, just with the fact that you don't like it.
 
Random thought:
Some of the arguments are basically saying that it's wrong for Tesla to advertise power amounts that we can never see or utilize. I won't dispute that here. However, no one seems to care that every other manufacturer does the same thing, even when using SAE net HP. This is due to drivetrain losses. Tesla uses a direct gearing drive with minimal losses, so the power at the motor shaft is much closer to what you, as the driver, get to utilize. Other manufacturers use transmissions and differentials that rob 15-20+% before this power get to the wheels. So you, as the driver, really never experience the full power of the motor. Why is Tesla crucified for not giving us the full power advertised, yet everyone else gets a pass? I realize it's a different reason why the full advertised power isn't available to the rear wheels, but the end result is the same.
 
My definition of GROSS when applied to both ICE and EV is that both are getting as much fuel as the engine or motor can take before any power robbing attachments and accessories are applied to arrive at NET. My bigger point is that I'm willing to accept something from Tesla less rigorous than NET even though I shouldn't. I guess i'm just a push over and easily satisfied :)

If P85D's battery output 525KW, I can guarantee most of the folks here would not be so upset about being intentionally lied. You might even see me throwing in discounts like "yea, but Tesla's AWD power train loss is less than typical ICE AWD losses, so give them a break". But the reality is they threw out a number that is so *far* from reality that no amount of handicaps or discounts can make up for it.
I was talking about GROSS power in context to this line, which is why I focus of the equipment and settings part of the definition:
"It is always unacceptable advertise horsepower that a car can never achieve under any circumstances......as it was sold(I have to add that little disclaimer because then you'll go on again about future battery upgrades allowing the P85D to make more power)."

I get that you would be okay if the battery was able to produced the measured power as installed in the car (as opposed to the shaft), but even that standard is more strict than what GROSS power represented. In the case of the P85D, the discrepancy was 480hp hypothetical shaft power with battery factored in vs 691 hp "motor power" which is a 30% discrepancy. That is on the same order as GROSS vs NET. Example given in article is the 1971 Cadillac Eldorado 8.2L V8 rated at 360hp gross and 235hp net which is a 35% discrepancy.
 
Random thought:
Some of the arguments are basically saying that it's wrong for Tesla to advertise power amounts that we can never see or utilize. I won't dispute that here. However, no one seems to care that every other manufacturer does the same thing, even when using SAE net HP. This is due to drivetrain losses. Tesla uses a direct gearing drive with minimal losses, so the power at the motor shaft is much closer to what you, as the driver, get to utilize. Other manufacturers use transmissions and differentials that rob 15-20+% before this power get to the wheels. So you, as the driver, really never experience the full power of the motor. Why is Tesla crucified for not giving us the full power advertised, yet everyone else gets a pass? I realize it's a different reason why the full advertised power isn't available to the rear wheels, but the end result is the same.

I agree 100%, though I didn't know what numbers to quote for % loss in drivetrain.
 
Random thought:
... However, no one seems to care that every other manufacturer does the same thing, even when using SAE net HP. This is due to drivetrain losses....
You must be skipping or misreading about 25% of sorka's posts which have addressed that multiple times. (Short version: he's conceded ignoring drivetrain losses but even with that gift, the numbers are quite off the mark.)
 
I still don't get why a 70D is rated way less than the sum of its motors but a P85D isn't.

but nobody wants to answer that and the only person I've seen acknowledge the question suggested we shouldn't confuse matters. There's no confusion in my mind, it's exactly the same logic, or should be.
You dismissed my previous answer but here it goes again.
During the P85D launch in October 2014 until the late March / early April 2015 time frame (when the 691 hp thread appeared) the only number advertised for all models was motor power, namely the sum of the motors (note that 70D did not exist back then, although the 60D did):
http://www.greencarcongress.com/2014/10/20141010-tesla.html
https://web.archive.org/web/20150330020918/http://www.teslamotors.com/models#battery-options

When the 70D had a motor power number, it was advertised at 514hp motor power (the sum of its motors). Although that was right at the transition point, where they had added back a lower system power rating also:
http://www.teslamotorsclub.com/show...o-691HP/page39?p=970726&viewfull=1#post970726
http://www.teslamotorsclub.com/show...91HP/page119?p=1115469&viewfull=1#post1115469

You can dismiss my point about why they switched away from motor power from the other models (namely the complaining about the 691hp number), but you can't ignore that they were rated under the same system for months.

Tesla removed the 691hp number some time in May, so the only time you might see the two numbers (70D using a lower system number and P85D using a motor power number) together is in April.
http://my.teslamotors.com/forum/forums/rip-691-hp

Your comment does not apply anymore to a person looking at the site since then, since a combined number for the P85D/P90D does not exist on the site anymore.
 
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You must be skipping or misreading about 25% of sorka's posts which have addressed that multiple times. (Short version: he's conceded ignoring drivetrain losses but even with that gift, the numbers are quite off the mark.)

Sorry, didn't feel like wading through pages of people complaining and disagreeing (on all the other threads). I know this discussion has been beaten to death...
 
This reponse is exactly what I was expecting here. Once more other manufacturer’s claims as simply dismissed without any proof what so ever. You and others simply apply Teslas 5C-rating as the universal law here without any references and in this case it is so obviously wrong.

Your cherry-picking of the top speed is perfect in this case. As you conveniently ignore the stated all electric 0-62mph times for the 918 Spyder which come in at 6.1seconds. Not far off from the Model S 70D which is listed as 328HP... Of course the 70D weighs more, but not that much more.

So how can a 918 Spyder perform that task with a 5C-rating? Wouldn't that imply battery power of a miniscule 34KW/45hp? Porsche is without any doubt applying a completely different C-rating than Tesla. Otherwise those 0-62mph figures are not even close to being possible....

Another relevant example, to prove this point, is the BMW i3 which is a lot lighter than the 918Spyder, has 125 kW (168 bhp) and does the 0-62mph in 7.2seconds. Of course not AWD, but much lighter than the Porsche.

For fun let’s say the 918 Spyder only had 125kw just as the BMW.. That would be a theoretical C-rating of 18C for the Spyder 918 according to your own math. That’s a whole lot more than the claimed 10C of Mercedes and the 5C measured for Tesla. And I strongly doubt 125KW would be anywhere close enough to propel the 918 Spyder 0-62mph in 6.1seconds. So most likely the C-rating used by Porsche is higher than 18 as well.

But I assume you and other here will just say "the Porsche can’t possibly do the 0-62mph times they list".. Otherwise your entire argument falls to pieces here.

Fun facts from your post:

70D weighs 916 lbs more than 918, which you say "not much more" (4608-3692=916)
i3 weighs 892 lbs less 918 which you say is "a lot lighter than 918"

Regarding the cherry-picking data, the horsepower and weight, as was mentioned many times, do not uniquely identify acceleration, as it depends on many other factors. Therefore comparing horsepower and weight of different cars does not accurately define the relative differences in the acceleration. So your examples are not very relevant.

The maximum speed, on another hand, is directly tied to the maximum available horsepower. A 3692lbs car needs much less than 286hp to have maximum speed of 93mph. If Porsche 918 motors are not limited by the battery, how come maximum speed is only 93mph? Note that this speed is not rpm limited, directly connected front motor has 16,000-rpm redline (good for 165mph), and rear motor connected through the 7 speed transmission.
 
Here are few details that I think worth noting:

The standard does not "specify motor capacity" it establishes procedure for rating of electric drivetrains.

My interpretation is the same as JB Straubel's and Tesla Motors Engineering, but arrived at independently, prior to JB Straubel's Blog post. The interesting part is that some members active on the threads relating to "missing horsepower" were aware of this regulation for quite some time, but, apart from Stopcrazypp, they did not care to carefully read through it, apparently because there was nothing there to support their views.

Your bullet list, aside from the first bullet that I addressed, has nothing to do with the Standard, just with the fact that you don't like it.

This is the list:


  • Tesla stated "691 hp motor power" on their website in multiple places. It did not state anywhere that "hp motor power" meant something other than hp produced by motors. There was no asterisk next to the horsepower spec stating that this is not actual horsepower produced by the production vehicle.
  • The only place ECE R85 was referenced was inside the owners manuals and even these didn't contain the that reference until after the P85D was already shipping. Are we to expect that prospective buyers doing their research are supposed find this reference first in the owners manual?
  • The subsystems page in the manual lists individual motor powers and does not add the front and rear motors together. In fact, if you add up front and rear motors, you get 728 hp, not 691 hp.
  • Publications for over a year now have been publicizing 691 hp, not "hp motor power". Why hasn't tesla corrected them and why are they all still quoting 691 hp when the car only makes 480 to 555 hp depending on state of charge?
  • The sales people repeatedly stated the P85D makes "691 horsepower" without ever adding the term "motor power".
  • Elon Musk himself has been quoted as saying the P85D has 691 hp and did not use the term motor power. He's also been quoted as saying the P85D has 50% more power than the P85.
  • If they were going to list a combined horsepower number, they had an obligation to list the power that the P85D actually makes. They do for the other Model S trims. In addition, since the P85D is the only Model S to lose power as the SOC declines in it's normal daily driving range, they should have clarified that the 555 hp is only at 90% SOC or greater and that below that, power will decline as charge declines. This is not true on the other Model S variants until you get much deeper in to charge state.
  • Ignoring repeated multiple letters and emails over MONTHS asking for clarification about the horsepower rating. We get responses for everything else we ask but those that inquired about this got nothing. If they were being so above board about this with nothing to hide, how come they refused to respond to the question of "why is my car only making 480 to 555 hp (depending on SOC) when it was advertised at 691 hp"?
  • Just because they test according to R85 to arrive at motor power ratings doesn't mean they get to use that in place of actual horsepower specified. Nowhere in the regulation does it state you can substitute horsepower rating of the vehicle with motor power capability of the drivetrain (with a power source not supplied). These are two entirely separate things. One is the actual horsepower produced by the vehicle. The other is an irrelevant specification that can't be reached with the shipping battery. It's only possible value would be knowing your drivetrain could handle more power if a battery with more power became available in the future.

You never addressed the first item.

Everything on this list represents the facts.

I spent a great deal of time researching the P85D in forums and articles and never ONCE ran across ECE R85. If it was mentioned here, I would have either had to read every single message to find it or search for it knowing in advance what I was looking for. Instead Tesla never bothered to specify anything about R85 on their website or product literature. But it's irreverent because it has nothing to do with the horsepower of the vehicle. You can disagree all you like but that fact will never change.

Tesla advertised 691 hp and now we know they intentionally mislead us(see list above).

- - - Updated - - -

I was talking about GROSS power in context to this line, which is why I focus of the equipment and settings part of the definition:
"It is always unacceptable advertise horsepower that a car can never achieve under any circumstances......as it was sold(I have to add that little disclaimer because then you'll go on again about future battery upgrades allowing the P85D to make more power)."

I get that you would be okay if the battery was able to produced the measured power as installed in the car (as opposed to the shaft), but even that standard is more strict than what GROSS power represented. In the case of the P85D, the discrepancy was 480hp hypothetical shaft power with battery factored in vs 691 hp "motor power" which is a 30% discrepancy. That is on the same order as GROSS vs NET. Example given in article is the 1971 Cadillac Eldorado 8.2L V8 rated at 360hp gross and 235hp net which is a 35% discrepancy.

Not sure where you're getting 30% or 480 hp. At 30% SOC the battery maxes out around 355 KW or just under 480 hp. This doesn't represent a 30% drivetrain loss.

- - - Updated - - -

Random thought:
Some of the arguments are basically saying that it's wrong for Tesla to advertise power amounts that we can never see or utilize. I won't dispute that here. However, no one seems to care that every other manufacturer does the same thing, even when using SAE net HP. This is due to drivetrain losses. Tesla uses a direct gearing drive with minimal losses, so the power at the motor shaft is much closer to what you, as the driver, get to utilize. Other manufacturers use transmissions and differentials that rob 15-20+% before this power get to the wheels. So you, as the driver, really never experience the full power of the motor. Why is Tesla crucified for not giving us the full power advertised, yet everyone else gets a pass? I realize it's a different reason why the full advertised power isn't available to the rear wheels, but the end result is the same.

Tesla's drivetrain loss is less than other ICE vehicles. I'm willing to cut them a discount for that. But it's nowhere near enough to make up adverting 691 hp when the car only makes 480 (30% SOC) to 555 (90% SOC) at the battery. For example, the Hellcat is speced at 707 flywheel hp but really makes 750 flywheel hp and dynos 635 at the wheels. This is how most manufacturers of high horsepower cars rate power these days. They almost always underrate their engines for insurance purposes. The RS7 dynos 470 at the wheels and makes 560 at the flywheel. They've either also underrate the SAE NET flywheel hp or their AWD system only loses 16%. You take your pick.
 
This is the list:


  • Tesla stated "691 hp motor power" on their website in multiple places. It did not state anywhere that "hp motor power" meant something other than hp produced by motors. There was no asterisk next to the horsepower spec stating that this is not actual horsepower produced by the production vehicle.
  • The only place ECE R85 was referenced was inside the owners manuals and even these didn't contain the that reference until after the P85D was already shipping. Are we to expect that prospective buyers doing their research are supposed find this reference first in the owners manual?
  • The subsystems page in the manual lists individual motor powers and does not add the front and rear motors together. In fact, if you add up front and rear motors, you get 728 hp, not 691 hp.
  • Publications for over a year now have been publicizing 691 hp, not "hp motor power". Why hasn't tesla corrected them and why are they all still quoting 691 hp when the car only makes 480 to 555 hp depending on state of charge?
  • The sales people repeatedly stated the P85D makes "691 horsepower" without ever adding the term "motor power".
  • Elon Musk himself has been quoted as saying the P85D has 691 hp and did not use the term motor power. He's also been quoted as saying the P85D has 50% more power than the P85.
  • If they were going to list a combined horsepower number, they had an obligation to list the power that the P85D actually makes. They do for the other Model S trims. In addition, since the P85D is the only Model S to lose power as the SOC declines in it's normal daily driving range, they should have clarified that the 555 hp is only at 90% SOC or greater and that below that, power will decline as charge declines. This is not true on the other Model S variants until you get much deeper in to charge state.
  • Ignoring repeated multiple letters and emails over MONTHS asking for clarification about the horsepower rating. We get responses for everything else we ask but those that inquired about this got nothing. If they were being so above board about this with nothing to hide, how come they refused to respond to the question of "why is my car only making 480 to 555 hp (depending on SOC) when it was advertised at 691 hp"?
  • Just because they test according to R85 to arrive at motor power ratings doesn't mean they get to use that in place of actual horsepower specified. Nowhere in the regulation does it state you can substitute horsepower rating of the vehicle with motor power capability of the drivetrain (with a power source not supplied). These are two entirely separate things. One is the actual horsepower produced by the vehicle. The other is an irrelevant specification that can't be reached with the shipping battery. It's only possible value would be knowing your drivetrain could handle more power if a battery with more power became available in the future.

You never addressed the first item.

You are listing a different bullet list than the one I was responding to in this post. I responded to the first bullet in the list.



I spent a great deal of time researching the P85D in forums and articles and never ONCE ran across ECE R85. If it was mentioned here, I would have either had to read every single message to find it or search for it knowing in advance what I was looking for. Instead Tesla never bothered to specify anything about R85 on their website or product literature. But it's irreverent because it has nothing to do with the horsepower of the vehicle. You can disagree all you like but that fact will never change.

This is just flat out wrong, Stopcrazypp brought it up in TMC conversations with you several times; apparently you dismissed it even without looking into it, no wonder you do not remember. Here are few references to refresh you memory. It seems that you were finding only stuff that you wanted to find.

08/18/2015
http://www.teslamotorsclub.com/show...-Up-to-691HP?p=1115882&viewfull=1#post1115882
08/18/2015
http://www.teslamotorsclub.com/show...-Up-to-691HP?p=1115945&viewfull=1#post1115945
08/19/2015
http://www.teslamotorsclub.com/show...laint-letter?p=1117782&viewfull=1#post1117782
 
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This is just flat out wrong, Stopcrazypp brought it up in TMC conversations with you several times; apparently you dismissed it even without looking into it, no wonder you do not remember. Here are few references to refresh you memory. It seems that you were finding only stuff that you wanted to find.

08/18/2015
http://www.teslamotorsclub.com/show...-Up-to-691HP?p=1115882&viewfull=1#post1115882
08/18/2015
http://www.teslamotorsclub.com/show...-Up-to-691HP?p=1115945&viewfull=1#post1115945
08/19/2015
http://www.teslamotorsclub.com/show...laint-letter?p=1117782&viewfull=1#post1117782

Pretty sure sorka meant that ECE R85 never popped up before all these discussions about the hp controversy started, therefore a potential customer could not have known about this regulation while researching the vehicle he's about to purchase.
 
Drivetrain loss has nothing to do with this conversation so stop bringing it up. P85D does not ever produce 691 HP anywhere. Not even motor power. It just doesn't. Who cares about other EV manufactures. I bought and paid for the P85D. If I bought a different manufacturers EV I would be complaining there, if I was misled the same way. If other manufacturers mislead the same way, this does not make it right. It is still misleading. Horsepower this horse pictur Horse power is horsepower. You either make it or you don't.
 
You are listing a different bullet list than the one I was responding to in this post. I responded to the first bullet in the list.

The bullet list I was referring to is the one I just quoted from here:

Tesla blog post: AWD Motor Power and Torque Specifications - Page 38

But even on the other older list, you still never addressed that item either. Characteristic 1.3 monomotor/multimotors does not address whether you can add the individual motor ratings together and indeed even Tesla doesn't do this in the owners manual where they declare that they've tested in accordance with that regulation. They list the motor ratings separately and not combined(which is bullet #3 BTW) . You just simply requoted the characteristic without addressing this at all.


This is just flat out wrong, Stopcrazypp brought it up in TMC conversations with you several times; apparently you dismissed it even without looking into it, no wonder you do not remember. Here are few references to refresh you memory. It seems that you were finding only stuff that you wanted to find.

08/18/2015
http://www.teslamotorsclub.com/show...-Up-to-691HP?p=1115882&viewfull=1#post1115882
08/18/2015
http://www.teslamotorsclub.com/show...-Up-to-691HP?p=1115945&viewfull=1#post1115945
08/19/2015
http://www.teslamotorsclub.com/show...laint-letter?p=1117782&viewfull=1#post1117782

Those are recent discussions many months after the controversy started. Not discussions indicating folks knew this early on before the and just after the P85D shipped. Not even before Tesla removed the combined 691 hp rating off their website.

- - - Updated - - -

Pretty sure sorka meant that ECE R85 never popped up before all these discussions about the hp controversy started, therefore a potential customer could not have known about this regulation while researching the vehicle he's about to purchase.

Yup. I thought it was clear enough but apparently not.