Oct 7, 2015
brianman I think that was Roadster. And TEG will probably chime in to remind me that it was a myth or something.�
Oct 7, 2015
dsm363 Really. You know the answer to that and how Tesla came to that number.�
Oct 7, 2015
Stoneymonster We are discussing the motor power ratings of individual motors, yes.
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Here's an old post claiming they are different: Motor-battery combo performance differences S60, S85, and P85. Later posts say they are not. I think you are right and they are not different. Does that mean the motor power figure includes the inverter?
The first post in that thread is interesting too, directly talks about thoeretical motor capabilities (motor power) and actual.�
Oct 7, 2015
Luclyluciano All how does changing the fuse and the software change the actual max rating on the motors from the 691 original motor HP?
lets not complicate the conversation by bringing in lower HP cars motor HP ratings. The P85D and the P90DL have the same motors and inverter.�
Oct 7, 2015
brianman @dsm (Since he's clearly reading this thread...)
As I understand it, one of the arguments is "People should have done the research so that they understand what they're buying, etc." I think it's abundantly clear that (1) there is room for confusion about what the P85D and P90D products offer, (2) there are a lot of now informed people on this subject, (3) if Tesla doesn't update/add-to the wording there will be more buyers confused going forward, and (4) that could be improved but it is possible Tesla won't take action.
Starting a new thread is probably a bad idea. Putting it in this thread is probably a bad idea. So, how about this proposal:
How do you feel about a Wiki page that captures "what we think we know" about the Model S w/r/t this 691hp drama? What I'm thinking is something that lays it all out there. I'd love to be able to point to 1 page that is readable by non-experts and educates them on the subject quickly and correctly.
I'm thinking a format that starts with:
(1) What Tesla publicly stated
(2) (Maybe) What Tesla previously publicly stated
(3) Links to threads that have research (I'm talking the REST data, vbox, charts, etc.)
(4) "Curated" text that captures our collective current understanding
By "curated" I mean we could pick a handful of people to act as a committee to write the language.
I think it would be a good first step in putting this topic to bed, or at least finding common ground and focusing future discussion.�
Oct 7, 2015
Stoneymonster We aren't complicating anything, we're having a side conversation.�
Oct 7, 2015
brianman I'm not certain we know this for the most recent P85D vehicles. It's completely possible (and perhaps likely) that when they first announced P90D they already had P85D drive units coming off the line that were better/different than previous P85D drive units.
I'm not trying to suggest that people should start tracking VINs and such. I'm just saying that we don't know for certain one way or another, so we probably shouldn't start with that assumption.
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Read post 13.
Motor-battery combo performance differences S60, S85, and P85 - Page 2
Hah, it's like I read his post before I posted earlier. (But I didn't...no really... well, at least not in 2015.)�
Oct 7, 2015
Luclyluciano No I do not. That is why I am asking. If they have the same motors and inverters between the P85D and the P90DL where does the extra 70 +motor HP come from. I thought 691 HP was the MAX motor Hp rating for the motors. That's why they were advertised.�
Oct 7, 2015
Stoneymonster Yup, just got there
�
Oct 7, 2015
Luclyluciano What are you talking about? I have a P85D with an advertised 691 HP motor rating which the battery/fuse system cannot satisfy. So I upgrade the fuse & software for $10k and suddenly I have 761 HP motor power with all the same motor hardware ? How is that possible?�
Oct 7, 2015
brianman That's not what I was saying. I lost track of when P90D was launched, but let's say May.
I was suggesting that a May P85D drive unit pair might have P90D specs (762) while an April P85D drive unit pair has P85D specs (691). Tesla has done stuff like this before -- both for features (Supercharging, Autopilot sensors, etc.) and spendy hardware ("40/60" had 60 kWh batteries that were software limited to 40 usable).
Furthermore, they might do like chip manufacturers do -- build P90D (762) drive units exclusively, test them, and software limit (691) the "weak ones".
There's all kinds of "it's not that simple" stuff that comes into play when you're trying to minimize costs, optimize throughput, maximize profit margins, etc.�
Oct 7, 2015
Luclyluciano That cannot be possible. The current P85D is still Advertised as 691 HP motor Power. It doesn't actually produce that 691 HP. It is not limited to the 691 HP power. It is limited to 550 HP.�
Oct 7, 2015
brianman I think we define "possible" differently.�
Oct 7, 2015
stopcrazypp "Motor power," like the ECE R85, includes the motor controller and inverters. This would be similar to how crate motors are sold with ECUs attached. When you keep that in mind the numbers are pretty straightforward.
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Simple: they have different software. The 70D/85D motors went from 188hp "motor power" to 259 hp "motor power" just with a software update.
The number more accurately is the power of the motors inclusive of the motor controllers and inverters. That is how ECE R85 measures things. That means any software updates on the motor controller will change the motor power rating.�
Oct 7, 2015
Luclyluciano
What do you mean? Spell it out.
Where does this extra 70 HP motor power come from when the motor hardware Is identical to the P85D and it is rated at 691 max Hp motor power all the while putting out 550 HP.
If the upgrades produce an extra 70 Hp then the P90DL should be advertised as 550 HP + 70 HP=620 Hp with still the rated 691 HP MOTOR POWER.�
Oct 7, 2015
stopcrazypp He's saying the motor hardware may not be identical between a P85D from back when they were advertising the 691 hp number and a P90DL or P85D rolling out of the factory now.
Like with the battery pack (which has gone through many revisions), it would be no surprise for Tesla to make continual changes to the motor (I believe from the motor noise issue threads they have different motor part numbers for a while already).
However, as I put it, the simpler explanation is because like ECE R85, the "motor power" includes the motor controller/inverter.�
Oct 7, 2015
AWDtsla It's like I'm reading the same thing over, and over, and over. Double check the timestamps. Yes new posts... hmmm�
Oct 7, 2015
sorka You clearly don't understand how this tax credit works. This is not a deduction. You get to take the credit regardless of whether you itemized or took the standard deduction as long as you have *any* tax liability after that. If you have more than $7500 after your deductions, you get to take the entire amount otherwise it's whatever you have left under $7500.
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But apparently you didn't.�
Oct 8, 2015
Soolim Are you sure of that ECE R85 definition for "motor power" including the drive controller?�
Oct 8, 2015
Luclyluciano
I understand and prrfectly how some of you are saying that PERHAPS the motors are different, perhaps the software is brings out more HP from the motors but let's get a few things straight.
The P85D motor is RATED at MAXIMUM 691 HP motor power. It's a rating similar to the rating of a lightbulb. This is supposedly how they rate electrical motors. This rating is like a maximum output CAPABILITY and LIMITATION rating of the physical motors themselves, provided the the rest of the system could feed this motor. But the system cannot. And therefore the actual motor OUTPUT is only 550 HP. Thus the controversy.
My car is equipped & Advertised with this motor CAPABILITY/LIMITATION.
Tesla says they will change my fuse and software and VOILA my motor now magically has a maximum capability/limitation rating of 762 HP motor power in my P85DL yet it really does not actually produce this output, it's probably more around 600 actual HP.
My point is the motor's physical maximum CAPABILITY/LIMITATIONS have not changed at all and this is how they rate these electrical motors. It's CAPABILITY & LIMITS remain the same and are constrained by the rest of the system. So how does my P85D motor change its rating to 762 HP motor power by changing a couple of items in the system.�
Oct 8, 2015
vgrinshpun It is pretty clear that it is the case. My advice is to invest some time into reading through applicable portions of ECE R85, and decide for yourself. The subject is covered in Section 5.3, Annex 2 and Annex 6.
If you'd like a summary, highlighting the exclusion of the battery limitation, you can read through this post.�
Oct 8, 2015
gavinwang I think you should stop sugarcoating it. There is absolutely no defense for TM to list a spec that the car, under no circumstances, will ever deliver but average customers naturally assume it will. It's equivalent to quoting a graphic card's highest resolution but omitting the fact that the laptop's LED panel is only capable of displaying half that resolution.
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Bragging about something that is only occasionally achievable is called marketing; Saying something that is NEVER achievable but letting people believe it is, is dishonesty and deception. The issue here is P85D can never ever deliver that 691 HP. I'm really shocked by a number of people here who can't discern this difference.�
Oct 8, 2015
vgrinshpun I have a question about your analogy. Do you think that high resolution of the graphic card in this laptop will ever has any use if the LED panel is only capable to display half of this resolution?
What specs do you think this laptop should display?�
Oct 8, 2015
stopcrazypp Yes. It is very clear cut about that.
Look at page 42, Table 1. It clearly lays out what must be attached to the motor that must be "standard-production equipment". The No. 2 item is: "Speed variator and control device" / "Yes: Standard-production equipment".
http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2013/R085r1e.pdf
Also on page 4 describing scope: "The electric drive trains are composed of controllers and motors and are used for propulsion of vehicles as the sole mode of propulsion."
The point of contention has been the No. 1 item in Table 1, which says: "DC voltage source" / "Voltage drop during test less than 5 %". It notably does not say "standard-production equipment" for that line (to make it clear "DC voltage source" could be a battery, a power supply, a fuel cell, a supercapacitor, etc). Also, the scope notably does not include "DC voltage source".
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There are two separate points:
1) My point is that the 691hp motor power rating is inclusive of the motor controller. That means even if the motor hardware is unchanged, a software change that changes the control strategy (a concrete example would be torque sleep) or parameters (such as current and thermal limits) can change the overall rating. The most concrete example is the individual 85D motors going from 188hp motor power to 259hp motor power just from a software update.
2) Brian's point is that your P85D motor may not have changed its rating. All Tesla has done is changed the rating of motors rolling out of the factory since the P90DL launch (deliveries happened somewhere in mid-August 2015). No where did Tesla say they are changing the rating of pre-Ludicrous P85Ds. So his point stands: it is not impossible for the motor hardware to have changed between a pre-Ludicrous P85D vs a post-Ludicrous P85D/P90D, and such a change may have been the cause of the change in ratings for the P85D/P90D delivered somewhere in mid-August.�
Oct 8, 2015
Dwu0212 - - - Updated - - -
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Yes! Exactly!
Instead of using common sense, they play word games and making excuses for Tesla that are laughable. I gave up explaining to them, sometime people are blind to truth�
Oct 8, 2015
Luclyluciano
Nowhere does Tesla say only CERTAIN P85Ds will be able to go ludicrous with the upgrade... Show us a link as proof that states this. Where are you coming up with this?�
Oct 8, 2015
Andyw2100 I'm pretty sure that wasn't what he was saying.
I think their point is the numbers on the Tesla website would be referring to sales of new cars, which could, conceivably, have different motors from the older cars (though there is no evidence of that--it remains only a possibility.)
I don't believe the numbers published on the website have ever been represented as what the numbers would be for an original P85D that was later updated to Ludicrous. In other words, the numbers on the website are for cars coming from the factory with that configuration.�
Oct 8, 2015
SDRick This is a simple question. If it was your company's laptop, what do you think would be the proper advertised spec(s)?�
Oct 8, 2015
stopcrazypp I see where the confusion comes from. The Ludicrous retrofit does not necessarily change the motor power specs. As Andy puts it, no where does Tesla say that the Ludicrous upgrade will change the P85D's motor numbers or that the numbers currently posted apply to P85Ds with the Ludicrous retrofit.
In fact, the current pre-order page makes it clear that a P85D upgraded to Ludicrous will not preform the same as a P90D with Ludicrous from the factory.�
Oct 8, 2015
AmpedRealtor If you check the drive unit serial numbers, they are constantly being revised. It's quite possible Tesla made some revisions to the electronics, but not the motor itself, to achieve the higher rating. What's on the web site doesn't mean that your P85D motor specs have changed. Only the specs of currently shipping motors may have changed.�
Oct 8, 2015
stopcrazypp There are useful reasons to quote a graphic card's highest resolution regardless of the included panel's resolution (to clarify I'm talking about the case of quoting both numbers).
1) There is a video output that supports external screens of higher resolution. Analogy with Tesla is the pack is swappable and upgradeable, so there are ways to utilize higher power available from the motors/controllers.
2) Graphics benchmarks are frequently done in a resolution normalized way. For example, the iPhone for has a lower resolution than most other smartphones, so in some benchmarks that gives them a huge advantage. However, if you care about the capability of the graphics chip itself, then you test with a benchmark that renders at a higher resolution than the iPhone can display. This is called an "offscreen" benchmark. ECE R85 may be that analogy (a test that doesn't include the battery).
3) Sometimes you have to display something that is at a higher resolution than your display (down conversion). For example, 1080p/2K/4K movies can be higher resolution than many displays and it is important to people to know if the graphics card can process such movies.
As for not advertising the screen resolution at all (quoting only one number), it really depends on the conventions used by the industry. It appears from the very first laptop, the screen was advertised with a resolution spec (52x24 character).
https://en.wikipedia.org/wiki/History_of_laptop
http://www.oldcomputers.net/osborne.html
Whereas for ICE vehicles, until the 1970s, the power advertised only considered the engine (SAE gross power) until the switch to SAE net. For the EV world, the standards have not been established yet.
http://ateupwithmotor.com/terms-technology-definitions/gross-versus-net-horsepower/
In a way, even SAE net is not a 1-to-1 analogy. For a monitor or laptop, we know the ultimate resolution we will see as an end user. For a car, we don't know the ultimate power we see (which is wheel horsepower). Instead, the numbers we see advertised are at the motor shaft (which we as a user will never see).�
Oct 8, 2015
Soolim New to this controversy and thanks for the link. After reading the parts your quoted, I am puzzled at why Tesla chose to label the motor Hp of the 70D, 85D and P85D in different manner as illustrated by pass threads. Had Tesla provided the same data i.e. listing the front and rear motor Hp of all models consistently, any doubt on its intent to encourage buyers to choose 85D over P85D due to higher Hp would be greatly diminished. Buyers would have a more consistent metrics to compare between models of Tesla, even without knowing the technical aspect of ECE R85. Now if they want to compare the motor Hp of EV to Hp of ICE, then more education is required. An "*" on the motor Hp data to direct the buyer to refer to ECE R85 will suffice imo.�
Oct 8, 2015
stopcrazypp I have been following the history of this. Starting from October 2014 with the launch of dual motors, Tesla only advertised with combined motor power for all models (adding motor power of dual motors). Starting in March/April 2015 (which coincides with the thread complaining about the 691 hp rating of the P85D) Tesla removed the combined number. They also changed to advertising the system numbers along with motor power numbers (except for the P85D). You can look at the internet archive to verify (although it doesn't show 2014 pages correctly so only 2015 can be verified) and also press numbers as of October 2014 launch. I have posted before with links, but it'll take a while to dig up.
Here's one quick example:
http://www.greencarcongress.com/2014/10/20141010-tesla.html
The inconsistency appears to have been ironically introduced in response to the complaints about the P85D number, whereas before it was consistent.�
Oct 8, 2015
Luclyluciano
That's interesting. Where did you see that? I was under the impression they would perform the same. Therefore the upgrade. I thought the only difference was the range difference. Link please....�
Oct 8, 2015
brianman Tesla Accessories and Charging Adapters LUDICROUS MODE ONLY (P85D) - PRE ORDER DEPOSIT
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Ok, I'll bite. I've shopped for laptops every few years since the 1990s.
Can you point out some links to some current laptop providers pages that show the GPU resolution but not the screen resolution? I'm honestly curious if there's anybody that does that.�
Oct 8, 2015
AmpedRealtor LOL!�
Oct 8, 2015
stopcrazypp Sorry I missed the link. It is here:
"This upgrade represents an estimate 10% increase in power over the already insane P85D, provides for a 0.2 second improvement over both the 0-60 mph and the quarter mile time, from your current vehicle performance. (The retrofit will not be an exact equivalent performance spec as a new P90D.)"
http://shop.teslamotors.com/products/model-s-ludicrous-mode-pre-order
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That is not what I am saying, perhaps I should rephrase. I am quoting examples where knowing a GPU resolution number that is higher than the screen resolution is useful. It is not a completely worthless number, just like how motor power is not a completely worthless number (as people have been suggesting).
However, in terms of industry convention for laptops, the resolution quoted is the screen resolution the user sees (even from the very first laptop), not the GPU.
That is not the case for cars. Until the 70s the number quoted was engine only, and even today the number quoted is not something a user can see (it is a shaft number, not the wheel number). Those are why the analogy doesn't fit in with the EV case. While people may find it unacceptable to quote only a GPU resolution and not the screen resolution they see (and this has been this way from convention), people have not found it unacceptable to quote only an engine number or a shaft number, even though the wheel number is the only number they can actually verify.
The closest analogy I can find to shaft vs wheel power is with TVs. There are 1080i TVs that actually have 768 pixel tall panels but most people would not know that.�
Oct 8, 2015
gavinwang No, most people do know what the "i" means in 1080i, because there is usually a "1080p" next to it. I agree even ICE only advertises shaft power not wheel power, and loss can be non-negligible from shaft to wheels; however shaft power is at the least an output the car can put out at some point of the car in real life, whereas 691 on P85D is a thing the car can never produce at ANY part of the car, which means it's never real and never useful in real life. What if the battery was so bad and could only support 300HP peak output, instead of 550? Would you still find slamming 691 on the ad as the only number acceptable?�
Oct 8, 2015
vgrinshpun The major distinction between this analogy and the P85D power ratings is that while screen resolution uniquely defines characteristic which people pay money for, the total output including limitation of the battery (550hp) is *NOT* what defines the major selling point of P85D - 0.8s improvement in 0 to 60mph acceleration. This 0 to 60 acceleration, which is essentially what Tesla is selling in P85D and what it is charging the premium over 85D for, is absolutely defined by the motor hp per ECE R85, i.e. 691hp, *NOT* by the battery limit defined throughput of 550hp.
This is the major point which is very hard to grasp for anybody without technical (as in electrical engineering) background. All of the analogies I saw so far are really not valid. Essentially, the reason so many try to come with analogies (which are invariably wrong) is an indication of the fact that there is a lack of understanding and appreciation of the differences between EV and ICE based propulsion systems. I am hoping to carve time to demonstrate this clearly for anybody willing to give it a thought with an open mind, even without technical background.
The above reason for this analogy being flawed is a major, but not the only one. The second one is that while screen resolution is a fixed number, the battery power limitation is not. While a lot of people mention ambient temperature, state of charge and age of the battery, few if any realize that battery power output also depends on prior loading profile.
I've have mentioned these points before, but I believe very few people involved in this conversation understand/appreciate them.�
Oct 8, 2015
eloder So it's my fault that I didn't do the proper research?
You're 100% right. I did not do enough proper research; therefore I am in error. I, personally, am responsible--not Tesla's marketing. I'm not going to blame Tesla--and every single other car manufacturer in the world--for advertising a $7500 tax credit that I can never obtain, though, even though there's no physical way I can obtain that level of depositing performance as advertised in real-world conditions.
Hey, this seems eerily similar to another topic at hand that we're discussing...�
Oct 8, 2015
cynix Tesla advertises the price of the car both with and without the tax credit. If they similarly advertised the power rating of the car both with and without the battery limitations then I think a lot of people here would have been satisfied.�
Oct 8, 2015
SDRick
Yes, and just think of all the negative energy and aggravation that would have been avoided along with the hundreds of pages of ink dedicated to this topic..�
Oct 9, 2015
gavinwang We don't really need an analogy, just use common sense. Again, battery state causing the real output to vary is not the defense for advertising an output that the battery will never allow to happen. If you have a bucket with one short stave, you should tell people how much water that short stave allows the bucket to contain; you are free to ALSO tell people the hypothetical capacity of the bucket if there wasn't a short stave.�
Oct 9, 2015
stopcrazypp My point was that whereas the screen resolution represents what you see as an end user, the HP number quoted doesn't. For example, while the P85D loses 10% of its power by the time it reaches the wheels, a typical AWD ICE car is assumed at 35% loss.
Of course, having both a battery (or system) and motor number is the most ideal.
But I find the 691hp number acceptable because I knew what it meant and what it didn't. In practical terms, it tells me if I do a battery upgrade in the future, that is what the motors/inverters can support. I can see why however for people that assumed it meant a system power number and are of the opinion that all car manufacturers are required to advertise a system power number would find that unacceptable.
For a better part of a century, ICE car manufacturers have been advertising a number that the car can never produce in ANY part of the car and people found that acceptable also, given they knew that was the case. And in that case, it was even a number they can't legally get (requires running the car without a cat).
Also, knowing the individual numbers in the dual motor case is useful because the battery can output enough to support one at a time, while a combined system number would not reflect that. For example, an EV with a 300 hp battery and 300 hp front and rear motors adding to 600hp will perform better than one with 150 hp front and rear motors adding to 300hp, even though under a conventional rating, they would be the same number. I think this was the same motivation for Tesla (why they introduced it with the dual motors).�
Oct 9, 2015
WarpedOne No. Ideal is max acceleration curve with speed on X axis and known tested weight.
This is what I sense with my butt dyno when I go drive the car. And this curves tell everything about the car performance - max speed and acceleration strength at any speed below max. One can deduce acceleration time between any speed points.
1/4 time is a 'first degree derivative' of such chart. It tells a lot about cars performance, but it does not say anything about low/high speed acceleration strenght.
*Everything* else is only partial information with innumerable hidden factors that will affect performance I will get.
HP number is meaningless, people are just used to it and blindly believe it. But it doesn't say anything about performance really.
Lotus Elise is one of the best sports car out there. It has mere ~250HP. There are +400HP cars out there that handle like dead cows and waaaay worse than that humble else.
Not to mention cars like Ariel Atom with 180HP and insane acceleration.
In short: stop talking about power, HP, torque and similar B*llSh*t. Give me acceleration curve. Then I will know everything that is to know about some car performance except for transient factors (overheating...).�
Oct 9, 2015
Luclyluciano
Its fine that the you believe the HP rating of the Tesla is meaningless to Tesla buyers, even if it's not true but many of us understand what it means and don't need a graph to understand this performance on the Tesla should mean. Most of us know the difference between a Lotus and a Tesla and we are not comparing handling so no need for a strawman. Plus, 0-60 is not the only performance measurement.
Lets say the Lotus with the true output of 250 HP was advertised and promoted by salespeople as having 325 HP output and you bought the car believing this and you paid a premium for this belief. Would there be a difference then.
Most of what I have seen in this thread is nothing but strawman arguments. Perhaps from many who did not spend the extra dollars to buy the PD so they have no skin in the game. Bottom line the car as is, does not output the HP many were led to believe. As is, it never has and never will.
Now with all the real info out, it is obvious the car is quick off the line but it is not fast.�
Oct 9, 2015
sorka We obviously have very different butt dynos�
Oct 9, 2015
ERP The S2 Elise only has 190 hp stock, and even less torque. Its the supercharged versions which produce mid 200's at the crank. And despite the car's decent handling, that low horsepower is very apparent on any track with a few long straight sections. If it is not a tight track, a 400+ hp cow can put down better lap times.
For those interested, the stock Elise does not handle that well. To make the car safer for poor quality drivers, it was setup to understeer significantly from the factory. The car needs more front camber, wider wheels and R compound tires. The stock stocks/springs are also rubbish. But fix these issue and the car will hold 1.5 lateral g's and is truly a dream to drive. Then add the BOE Rev kit and bring power up to 300-400 hp and you have achieved driving nirvana.�
Oct 9, 2015
AmpedRealtor So maybe Tesla should present specifications that don't require a degree in electrical engineering to understand? Just thinking out loud.�
Oct 9, 2015
jpet I agree, it would be awesome if Tesla could provide these curves for each model so that we can finally start comparing a 85D to a P85D, P85D, P90D, P90D...
This way we could also compare these curves to the curves of ICEs (which have a significantly different form).
To come back to the media topic of this thread, if Tesla does not provide us these acceleration curves, car magazines or consumer organizations could do these tests in a stable environment and be of significant help to us, buyers.
As you are also indicating, the curve alone is not enough because I regularly see the yellow power limiter appearing in my P85D. It does not require more than a couple of minutes to get it limited to 240 kW. But you won't get it if you just launch the car. Try driving it at 100 mph for a couple of minutes and then do a kick down... Of course, being able to drive at these speeds is not the most important thing in the world.
Knowing the strengths and weaknesses of the car is relevant info for someone interested in buying a Tesla. No vendor will be eager to give info on its weaknesses and that's probably why we're having the P85D motor hp controversy discussion.�
Oct 9, 2015
whitex It's not that hard - the motors are capable of 691hp but the battery doesn't have enough juice to let them produce more than 550hp in ideal conditions. The car can go 50,000 miles on a single charge, but the battery will run out of charge in 200-300miles, depending on driving conditions. No electrical engineering degree required to understand.�
Oct 9, 2015
yak-55 Uh, no. No one upgrading from 85D to P85D is knowingly paying for the difference in claimed motor power as you understand it. Why would anyone pay such a premium for a specification difference they can never experience ?! Tesla is "selling" a lay interpretation of hp with a technical excuse. If they weren't selling hp and as you assert were only selling 0-60 acceleration, they would simply remove *all* the references to hp, or motor hp from their promotional materials. Unlike you, Tesla understands that "horsepower sells" and they are misrepresenting the real world difference in models precisely because they understand that.�
Oct 9, 2015
stopcrazypp The difference between the two models is Tesla is selling a car with a bigger motor in the rear that is capable of more power, even though the battery limits it overall. And in practical terms what happens is when there is more power demand on the rear wheels, the P85D can put out more than the 85D. That is precisely what the motor power number (as well as the individual numbers) was intended to convey. Also, P85D has more room for additional power after battery upgrades (for example Ludicrous retrofit), whereas 85D is already maxed out.
And if we move away from the focus on the P85D vs 85D, you can see how it applies to the other models:
S60 and S85 was rated the same motor power, showing they used the same motor/inverter.
S60D and S85D was rated the same motor power, showing they used the same motors/inverters.�
Oct 9, 2015
yak-55 In the car, when there is high power demand, the P85D motors can put out about 50hp more than the 85D motors. That is precisely the reality that is deceptively avoided by Tesla's references to motor power. The significant price premium between models is much easier to sell when the power differential between models is represented as being much larger than it is.�
Oct 9, 2015
Andyw2100 And only at high SOCs. The difference in HP decreases as the SOC falls, and if I recall sorka's numbers correctly, at 60% SOC or lower, there is no difference in HP between the 85D and the P85D.�
Oct 9, 2015
SDRick Ouch!�
Oct 9, 2015
sorka The difference is that the P85D was advertised with 315 more horsepower than the 85D when in reality it only has only up to 52 more horsepower(with no difference with both cars at 60% SOC). We didn't purchase the "room" for additional power with future battery upgrades which we'd *also* have to purchase. We purchased a car that was advertised with 691 hp as delivered.
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Peak power at lower SOCs. The P85D still puts out more power at lower RPMs (more torque) than the 85D at any SOC(where both cars have the same SOC). This means the P85D will still kill the 85D from 0-60 at 60% but there won't be any difference in a roll on from 60 MPH on the freeway.
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Strange, reply to message 558 is in message 557.
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And now message 558 has been removed.�
Oct 9, 2015
DougH I deleted my post because you explained your earlier response. You were just to quick.�
Oct 10, 2015
stopcrazypp Yes, if the front motor was running at max power, the P85D as a total can only output 50hp more than the 85D because of the battery, however in the case of torque sleeping the front motors, the P85D can output 200+ more hp on the rear motor. This difference would not be represented in a system number.
Now let's go back to a hypothetical world of system power (Tesla never focusing on motor power) to see how the numbers would look like.
2014 to early 2015
S60: 302
S85: 362
P85: 416
60D: ~300 (extrapolated from S60 ratio)
85D 6.1: ~360 (extrapolated from S85 ratio)
85D 6.2: 422
P85D: ~480 (extrapolated from P85 ratio)
Now
S70: 315
S85: 373
70D: 328
85D: 417
P85D: ~480 (extrapolated from P85 ratio)
With just system power number, the P85D only gets a ~60hp advantage over the P85 and 85D, but then Tesla doesn't get to illustrate how versus the P85 you are actually getting an additional 221hp motor in the front. With 85D, they don't get to illustrate the P85D rear motor is 200+hp more. I think that is why they used motor power.
Now with 20/20 hindsight, we can say that what should have done was advertise with a system number, and then the individual motor power numbers not combined together, which is what they are doing now (P85D is still missing system number and I already put the theory of the exception being there precisely because of P85D complaining). However, if you were a marketing manager back then, it would not be obvious this would be as big an issue for some people as we now know. And adding the two numbers is very intuitive too.�
Oct 10, 2015
gavinwang Please enlighten me with a few examples in RECENT history of automobiles that a ICE car couldn't produce the stated HP at ANY part of the car, AND the discrepancy was as big as 15-20%. It's not unexpected that we can't recreate the exact nitpicky conditions the carmaker uses to produce their stated spec ---- we might not be able to reproduce the maximum ranges stated for model S, that is quite okay, but it's totally a different matter that the car is IN THEORY incapable of and far from producing that spec, which is exactly the case for P85D.�
Oct 10, 2015
Dennis87 I did email a question to UNECE about the UN Regulation No. 85 if Tesla is allowed to just add together the max power net numbers and if the test include battery limitation. This is the answer.
�
Oct 10, 2015
yak-55 No hindsight is required. Tesla was no doubt in possession of all these facts at the time. Their marketing choices, in the face of these facts, stand in the historical record.
Hardly relevant, but if *I* were "a marketing manager back then" *I* would very much have known this would be a big issue. *My* proposal to show real world relevant system power numbers probably would have been shot down as "not conducive to hitting our P85D revenue and margin goals. Everyone will just buy 85Ds ..."
To Tesla's credit, they have made some recent improvements in their disclosure. However, they have (almost tortuously) avoided any accurate representation of the real world power differences between the P85D and other comparable vehicles. Potentially damaging the brand. Why roll around in the questionable practices of the industry if you're goal is to be a different kind of car company?�
Oct 10, 2015
AmpedRealtor Too bad Tesla doesn't explain it this way on its web site. Too bad owners have to seek out answers and look up regulation ECE XYZ12345 in order to understand that the numbers Tesla prints on its web site are, for lack of a better word, crap. Don't give Tesla the idea of marketing the range as 50,000 miles because I believe Elon would do so if he thought he could get away with it.�
Oct 10, 2015
dsm363 Can you name another car with a front and rear motor blended into an AWD platform?�
Oct 10, 2015
Soolim Porsche 918 comes to mind:
Gas engine rear = 608 hp @ 8700 rpm
Rear electric motor = 156 hp
front electric motor = 129 hp
Max system hp = 887 hp
0-60mph = 2.5 seconds
1/4 mile = 10 seconds @ 145 mph
top track speed = 214 mph�
Oct 10, 2015
gavinwang Thanks for jumping in, I was about to say the same. Many hybrids have two or more power units, one being an electric motor, the other a gas engine. BMW i8 has two electric motors plus one puny engine. Nonetheless, I have no clue what dsm363 meant to say.�
Oct 10, 2015
sorka 20% to 25% *used* to be typical numbers thrown around for AWD drivetrain loss years ago. I've never EVER seen anyone claim higher than that so I'd like to know where you found 35%?
For comparison, stock RS7's dyno around 470 at the wheels SAE corrected which puts them at about 16% loss. AWD ICE cars have come a long ways in the last decade with much more efficient gear designs and automatic transmissions that lose a fraction of what they used to due to better fluids that are lighter and thinner yet protect better...as well as other design improvements that increase efficiency.
Also, we need to be very careful when discussing power train loss from the engine to the wheels. Loss comes from two sources. 1) Friction losses(gears, fluid resistance, tire deflection, etc), and 2 ) intertial losses(the energy it takes to accelerate or decelerate drivetrain mass).
Dyno runs at static speed under an eddie current load will completely hide losses due to inertia as the dyno is measuring the amount of power to keep the engine at it's exact peak power RPM. In this kind of dyno, if you change a flywheel from a heavy to a lightened one, the dyno will not register this as a power increase because there's no change in speed and as such no acceleration of mass. But on a dynamic dyno run where you accelerate drivetrain mass, a lightened flywheel will show as more power. The less the load that the drivetrain has to push against, the faster the drivetrain will accelerate causing the proportion of friction loss to inertial losses to shift more towards inertial losses as intertial losses increase as you reduce the load against the drivetrain on the dyno. The percentage of drivetrain loss measured is the least on static runs because you *only* have he frictional losses. This is why rule of thumb losses are meaningless.
The P85D has much less drivetrain mass compared to the typical AWD ICE. As such the P85D has an advantage in an acceleration dyno run compared to the ICE that makes the same power because the P85D's drivetrain doesn't have to overcome as much inertia. This advantage disappears once you dyno both cars at a static speed (where both are making their peak power) but not accelerating mass.
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Holy smokes! You got an answer? Who exactly did you email? I emailed nearly the same question to [email�protected] twice and never got a response. The first part of that response is quite eye opening!�
Oct 10, 2015
dsm363 I meant to ask how they write the combined hp down. If the full hp of the ICE and electric motor are available at one time how do they advertise it? Is it the hp at the shaft?�
Oct 10, 2015
X-Wing Mid-Engine ICE / F & R Electric
Porsche 918
Acura NSX
Front ICE / Rear Electric
Acura RLX
Volvo XC90
Could they both be using the e-AAM eAWD technology?
Front and Rear Electric (Torque Vectoring Capable)
SLS AMG E-Cell
Porsche Mission E
The SLS AMG was supposed to go into production, not sure if any ever did. Basically the SLS AMG E-Cell and Porsche Mission E are the Germans signaling that they have not been slacking in the EV game.�
Oct 10, 2015
dsm363 Do they advertise the correct system hp at the shaft that the car can actually achieve is my question.�
Oct 10, 2015
X-Wing The system power is measured based on the combined simultaneous output of both powertrain.
Note that the peak system output does not necessarily have to occur at either peak ICE or EV output.
Gear ratio also needs to be factored in. But let's assume that both the ICE and EV have just one single gear. The peak system output in this case is 82HP at 60mph.
As to Tesla, Volvo XC90 or Koenigsegg Regera. The actual combined power is less than the combined max individual motor power. Which could look something like this.
Vehicle Speed ICE (hp) EV (hp) System (hp)
50mph 30 50 80 60mph 41 41 82 70mph 50 30 80
In the above example, the combined motor power is 100+300 = 400 hp. But the system power is only 75+300=375hp.
Vehicle Speed Front (hp) Rear (hp) System (hp)
10mph 50 100 150 30mph 100 200 300 50mph 75 300 375
The specific case with the P85D/P90D is probably more complicated, as that is limited by the output of the battery which is totally outside of my area.
To me a better analogy to this debate is if a manufacture ships an engine physically capable of making 1000hp, but had to be de-tuned to 700hp because the fuel pump and injectors cannot keep up. Can the manufacture still claim making 1000hp?�
Oct 10, 2015
vgrinshpun I am curious what was the question you asked in the e-mail - I think you should share it along with the response.
Regarding the answer, it is not clear why the responding person is focusing on Annex 6. Annex 6 is laying out the rules for testing drive train, and it does not make distinction of whether the drive train includes one or several motors. Annex 2, however, implies that a drive train could either have one or more than one motor:
�
Oct 10, 2015
AWDtsla If a manufacturer ships a car that claims 1000hp, and there is no legal speed at which it has the traction on any road to output that 1000hp, can they still claim 1000hp? *cough* hellcat *cough*. Should return it back to Dodge "I press the pedal but I don't accelerate like I have 707hp, I just see smoke"�
Oct 10, 2015
X-Wing Completely different argument. Yes, Dodge can claim 707hp because they are producing 707hp.
At exact what vehicle speed does the P85D produce a combined 691hp from both motors?�
Oct 10, 2015
vgrinshpun And the answer is no. Both MB SLS Electric and Porsche 918 list combined maximum power of the motors without considering limitation of the battery, exactly the same way as motor hp is listed by Tesla.
I've posted about the SLS here.
Regarding the Porsche, it lists combined motor horsepower as 286 (129+156+rounding error). It has 6.8kW battery, which will not be able to provide output of 286hp or 213kW, as it will require discharge at the rate of 213/6.8=31.3(C), which is way too high for the automotive application. For comparison Tesla maximum discharge rate is under 5C. Additionally, it is clear that two electric motors in Posche 918 can't deliver the combined output of 286hp because they are limited by the tiny 6.8kWh battery - the car electric only speed is limited to 93mph (car weights 3692lbs).
So it appears that the way Tesla listed motor horsepower is not only consistent with ECE R85, but is also consistent with the way other manufacturers (Porsche, Mercedes) list motor hp for EV multi-motor drivetrains.�
Oct 10, 2015
AWDtsla No, it's completely the same argument, unless your only application and single-minded focus on this one number is for a pissing contest.
The phrase dyno queen exists for a reason.�
Oct 10, 2015
supratachophobia Yes, because the system still outputs the advertised 707hp, 6 times during it's acceleration curve.
The Tesla does not, as shipped, with either battery option.�
Oct 10, 2015
X-Wing Clearly you have problem comprehending some of the concepts involved. A Dodge Charger Hellcat makes 707 SAE horsepower at the following vehicle speeds, according to FCA. Of course that is 707 HP at the crank.
Keep in mind that Tesla does have a single speed gearbox with reduction gear and by virtual of that design has minimal drive train lost.
Gear
Gear Ratio
Final Ratio
Overall Ratio
Engine RPM
KM/H
MPH
1st
4.71 2.62 12.34 6000 66.72
41.47 2nd
3.14 2.62 8.23 6000 100.08 62.20 3rd
2.1 2.62 5.5 6000 149.65 93.01 4th
1.67 2.62 4.38 6000 188.18 116.95 5th
1.29 2.62 3.38 6000 drag limited 6th
1 2.62 2.62 6000 drag limited 7th
.84 2.62 2.2 6000 drag limited 8th
.67 2.62 1.76 6000 drag limited Reverse
3.3 2.62 8.65 6000 95.23
59.19
But we are not arguing about wheel horsepower here, we are talking about system power of the two motors working in combination with their respective reduction gear ratio.
Once again, educate me please. At exact what vehicle speed does the P85D produce a combined 691hp from both motors? To clarify 691 combined horsepower from the electric motor right before said power is fed into their respective single speed gearbox. Just like the 707 horsies from the Hellcat right before said power is fed into the ZF 8-speed gearbox.�
Oct 10, 2015
stopcrazypp You are changing the argument. Your argument is that it is common sense for a manufacturer to never be allowed to advertise a number it can't produce in any part of the car (or alternatively for them to advertise a number at a component level rather than a system level). I am saying it is not and have given an example in the car world. There is no common sense reason why it is always unacceptable to advertise at a component level.
And in the ICE world, I should point out the convention has switched to SAE J1349 (aka net power) and SAE J2723 (aka certified power). There are no such conventions yet in the EV world and obviously those standards don't apply to EVs (as they assume the existence of an ICE). There are two working groups that are working to come up with one though:
http://standards.sae.org/wip/j2907/
http://standards.sae.org/wip/j2908/�
Oct 10, 2015
stopcrazypp I think the Fisker Karma can be thrown in there also. Although it is not AWD, the two traction motors are also synchronized through the road. For that I think it is fairly clear that car used the same rating method as Tesla (just added the power of the two motors together: 150kW+150kW = 300kW / 402 hp).
For the only dyno that was done it got 230whp.
http://www.fiskerbuzz.com/forums/13-fisker-karma/4601-maximum-power-karma.html
I think the SLS E-cell is the closest however, but unfortunately there are not enough tests done on that to know if it factors in the battery correctly or not. I don't believe there are even any 1/4 mile or 0-100mph numbers verified for that, much less a dyno.
I should note none of the examples so far they did use the "motor power" term to differentiate what they might be doing.
The examples given by others of hybrids that are synchronized through a gearbox doesn't really apply as we are not talking about gearing imposed limitations, but rather a battery imposed one. The existing SAE standard for ICE is able to factoring in gearing imposed limits, as evidenced by hybrids certified via existing standards:
http://standards.sae.org/cpgm2_latsaturn/
http://standards.sae.org/cpgm2_10tyesshy/�
Oct 10, 2015
Luclyluciano Sure, the hellcat is not AWD, but it still produces 700 HP and is very fast. So yes they can claim their 700 HP output because it is real.
My P85D is quick off the line because of high low end torque and immediate responsiveness but it does not produce 691 HP .�
Oct 10, 2015
sorka 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).
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And as such, Tesla could get away with advertising GROSS power at the battery (we're just going in circles over and over) and most of us would have been fine with it. Advertising 555 at >= 90% SOC would have been fine with me until a standard is agreed upon. Any standard of which would not allow them to declare the full 555 hp because any reasonable standard for EVs will require declaring maximum power at an average daily driving SOC and not not maximum SOC since we don't get to drive at maximum SOC for most of the time. In this case, that wouldn't effect an 85D, P85, or S85, but it would effect a P85D. It will of course require measuring power at the motor shaft which would of course be lower than 555 because of inverter conversion and electricity to kinetic energy conversion.
Tesla can sort of get a pass right now to use GROSS power at the battery since there isn't a defined NET standard that takes into account the entire vehicle as delivered (if you're going to believe Vlad's interpretation of ECE R85 not using the drivetrain battery).
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The Hellcat is way under rated and makes more like 750 hp at the flywheel. It's likely underrated for insurance purposes. This is typical of high power cars these days to claim less than actual.
635 rear wheel hp (stock)
Dodge Challenger SRT Hellcat Dyno Tested, May Be More Powerful Than Claimed: Video
642 rear wheel hp (stock red key)
More Hellcat Power? - Dyno Comparison | SRT Hellcat Forum
A 15% drivetrain loss (rear wheel drive) puts these around or over 750 hp at the flywheel.�
Oct 11, 2015
brianman 608+156+129=893hp vs.
Max system hp=887hp
So they can align the stars fully except for 6hp? Impressive.�
Oct 11, 2015
dsm363 Impressive but if I paid $1,000,000 for 893 hp I would feel cheated. That's what I gather is the main complaint on this thread. They are much closer than Tesla but still apparently not advertising correctly.�
Oct 11, 2015
darthy001 Well... Porsche actually lists battery power just as Mercedes. But I assume the right crowd here will dismiss those numbers just as they did with Mercedes since it doesnt fit the rest of their world view...
http://press.porsche.com/vehicles/2015/Tech-Specs-2015-Porsche-918-Spyder.pdf
Edit: seems like the battery experts Tesla are the only ones not showing these numbers. Strange indeed.....�
Oct 11, 2015
Laserbrain WTH did my post go...? Let's see if it disappears again...
So you say everybody is allowed to adopt Volkswagen's creative Diesel exhaust measuring techniques? Because you are saying wrong isn't wrong as long as others do it, right? Hey I could go and rob a bank because somebody else did it and got away with it - so robbing a bank cannot be wrong, right?
Wrong. A scam is a scam. And no amount of spinning will change this.
Or explain to me why even today the hp of the 70D/90D are given as combined hp while the P85D hp are not. There is only one explanation. One! A single word describes it. It starts with a "s".�
Oct 11, 2015
dsm363 Mod note: It's in moderation while being reviewed. Personal attacks are not called for.�
Oct 11, 2015
X-Wing Can someone please fill in the blanks for me?
If someone can fill in the blanks above, it will be greatly appreciated. I tried, but the best I have got is this so far.
Model
Combined Output (hp)
Front Motor Output (hp)
Front Motor Rev (rpm)
Rear Motor Output (hp)
Rear Motor Output (rpm)
Vehicle Speed
(km/h)
P85D 691
Model
Combined Output (hp) Front Motor Output (hp) Front Motor Rev (rpm) Rear Motor Output (hp) Rear Motor Output (rpm) Vehicle Speed
(km/h)P85D 691 Not At Any Speed Ever �
Oct 11, 2015
Soolim Not cheated if those numbers were published to the public, and the buyer can make an informed decision if the 6 hp is material or not prior to the purchase. Did Tesla provided the same level of detail to the public prior to the complain?�
Oct 11, 2015
brianman We interpret things incredibly differently then. Either that or you're intentionally trying to upset people.�
Oct 11, 2015
stopcrazypp My point was that GROSS power as used by automakers before the 1970s is a "horsepower that a car can never achieve under any circumstances......as it was sold". GROSS power allowed automakers to use different intake, exhaust headers (with no cat), ignition timing, carburetor/fuel injection settings, not present in the car as it was sold, as well as ignoring parasitic loads (including those required to run the ICE itself like oil and water pumps). It did not represent what the car can achieve as sold, but rather what a component (the engine) could achieve, yet that was found acceptable to people.
http://ateupwithmotor.com/terms-technology-definitions/gross-versus-net-horsepower/
So there is no common sense reason for that to not be acceptable. All it depends is on how the industry convention goes and right now we don't have an agreed upon convention for EVs in regards to advertising at component or system levels (there is typically no difference between the two however for most standard power EVs though, only for high performance ones).�
Oct 11, 2015
Andyw2100 The main difference, though, is that at that time all the car companies were doing the same thing. So the comparisons were still, essentially, apples to apples.
Now you have all the car companies using a different standard. A standard that is achievable in the cars. But since there is no EV standard yet, Tesla decides it's an OK idea to display the maximum power in a way that isn't actually achievable in the car, knowing that it will make the car look better by comparison than it really is.
That just wasn't right, any way you look at it.�
Oct 11, 2015
cynix You keep using the gross hp standard to back up your claim that people found it acceptable to publish a number that can never be achieved. Do you not realise that we stopped accepting it 40 years ago precisely because we found it unacceptable?�
Oct 11, 2015
vgrinshpun What you are apparently missing is that Porsche quotes battery power that requires a discharge of 33.82 times capacity (33.82C=230/6.8). The discharge rate is way too high to be sustained by this battery for any duration of the time which will allow notors to use this power. For comparison, assuming total throughput of the propulsion system in P85D to be 550hp (just grabbing the number used by Sorka) yields discharge rate of less than 5C. So Porsche lists peak power out of the battery, sustainable perhaps for a fraction of the second. The Porsche tiny (6.8kWh) battery can't deliver this power at the time when motors can use it. So Prosche electric motors can never deliver 286hp, because they are limited by the battery. In one sense this is exactly the same situation as with P85D, but if one wants to talk about misleading information, it is much more misleading with Porsche because they are listing max battery output which can't be achieved at the same point in time when motors reach their (max) rated power.
All of this becomes quite clear if, as I posted before, one notes that maximum electric speed of the 918 is only 93mph. Don't you think that a car that weights only 3692 lbs and has claimed 286 (electric) hp should have maximum speed much higher than 93mph?
And here is the irony this example demonstrates yet again that not only Tesla followed ECE R85 with the way they listed motor hp, they also followed the same practice as at least two other manufacturers of high power plug-in cars: Mercedes SLS Electric and Porsche 918.
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There is quite clear that there is no difference at all. The two other examples of high powered plug-in cars, Mercedes SLS Electric and Porsche 918, rate their drivetrains the same way as Tesla, just summing maximum output of the motors, without taking into account limitations of the battery, seemingly following ECE R85.�
Oct 11, 2015
aus Ford and Mazda have been forced to offer to offer compensation or buy back cars that didn't produce as much power as advertised many years ago.
As for the P85D, most people are going to expect a car that will go as fast as an ICE rated at the similar power to weight ratio.
They would also expect the car to dyno around 15-17% (20% for AWD) less than the advertised power (crank power).
The problem seems to be, there's no standard, such as SAE or DIN for rating power on electric vehicles.
This guys is hilarious. NWS language
�
Oct 11, 2015
vgrinshpun There *is* standard for rating EV drive trains, and Tesla follows it - ECE R85. Section 5.3, Annex 2 and Annex 6 cover ratings of EV drivetrains�
Oct 11, 2015
stopcrazypp Actually we don't know what other car companies are using, because none of those numbers have been verified with the vigor we have done with the P85D. As I point out, for lower power cars (which describe a large majority of non-Tesla EVs) battery limitations are not going to show up. So even if they used the same motor power rating standard as Tesla, there is no difference between the two numbers.
The unique part of the P85D is that Tesla puts such powerful electric motors into it, that it exceeds what the battery is capable of. The closest example I have seen so far is the SLS E-cell, but there is a lack of performance information on that car. There are some hybrids posted, but the hybrids use low capacity power optimized batteries and don't have combined electric motor power approaching 700hp.
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I'm using that example because it relates to the power issue directly and as a counter example to the notion that it is "common sense" for a component level specification to never be acceptable.
And as for the reasons why we moved away from gross power for the ICE, it was not because people found it unacceptable, but rather a whole lot of reasons in the 1970s (known as the "malaise era" in the automotive world) that made it advantageous for auto manufacturers to advertise a lower number. You can read the article I linked, but reasons cited include more stringent fuel economy, emissions, and safety standards (corresponding to the fuel crisis) and rising insurance costs. Someone brought up why they didn't switch back to gross afterwards, but I think automakers' reluctance to move from the status quo would easily explain that (and peer pressure would play a part too, there has to be a trigger point for an industry-wide move).
http://ateupwithmotor.com/terms-technology-definitions/gross-versus-net-horsepower/
As it relates to EVs however, the automakers have not established a convention yet for how they are going to advertise horsepower. Tesla chose to use numbers using the same test standard as ECE R85 (used in all their conformance certificates) when they released their dual motor vehicles. As I put elsewhere, when SAE finishes drafting their standard, the industry will likely use that.�
Oct 12, 2015
darthy001 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.�
Oct 12, 2015
sorka You keep missing my point. Would it be proper to list the total horsepower the car can make by listing the maximum battery output actually achieved? No. Of course not. This would result in 555 hp >= 90% SOC. The actual power at the motor shafts will be less due to conversion losses. My point is that if the P85D actually put out 525KW and Tesla claimed 691 hp, this would STILL be cheating, but it would at least have been a real horsepower figure achieved somewhere even if before accounting for inverter and electric to kinetic energy conversion.
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.
There is no NET standard for EVs right now that includes measuring horsepower at the motor shafts after accounting for the things that reduce power after the battery. My point is if they just want to bypass that and declare power upstream before any of that I'm fine with that. It would have at least been a real number. I'd still prefer actual horsepower quoted as measured from the motor shafts.
A NET power standard that takes into account these things plus the average daily driving SOC of the battery would be ideal and would provide the best apples to apples comparison to ICE vehicles.
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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�
Oct 12, 2015
JonG 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.�
Oct 12, 2015
X-Wing Still looking for the answers. Will these insist on 691hp being correct fill in the blanks above please?
Model Combined
Output (hp)Front Motor Output (hp) Front Motor Rev (rpm) Rear Motor Output (hp) Rear Motor Output (rpm) Vehicle Speed (km/h) P85D 691
By the way, dyno result from DragTimes shows 413hp max.�
Oct 12, 2015
Stoneymonster annnnd we're back to March on this thread.�
Oct 12, 2015
stopcrazypp 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.�
Oct 12, 2015
sorka 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.�
Oct 12, 2015
smac
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!�
Oct 12, 2015
scott jones 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�
Oct 12, 2015
vgrinshpun
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.�
Oct 12, 2015
DoctorJJ 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.�
Oct 12, 2015
stopcrazypp 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.�
Oct 12, 2015
lorih I agree 100%, though I didn't know what numbers to quote for % loss in drivetrain.�
Oct 12, 2015
brianman 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.)�
Oct 12, 2015
stopcrazypp 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/showthread.php/44691-P85D-691HP-should-have-an-asterisk-*-next-to-it-Up-to-691HP/page39?p=970726&viewfull=1#post970726
http://www.teslamotorsclub.com/showthread.php/44691-P85D-691HP-should-have-an-asterisk-*-next-to-it-Up-to-691HP/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.�
Oct 12, 2015
lorih 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...�
Oct 12, 2015
vgrinshpun 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.�
Oct 12, 2015
sorka 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 - - -
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 - - -
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.�
Oct 12, 2015
DillyBop i agree with those saying that we're not exactly forwarding the advent of sustainable transport with distractions like this.
let's keep our eye on the ball.�
Oct 12, 2015
vgrinshpun 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.
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/showthread.php/44691-P85D-691HP-should-have-an-asterisk-%2A-next-to-it-Up-to-691HP?p=1115882&viewfull=1#post1115882
08/18/2015
http://www.teslamotorsclub.com/showthread.php/44691-P85D-691HP-should-have-an-asterisk-%2A-next-to-it-Up-to-691HP?p=1115945&viewfull=1#post1115945
08/19/2015
http://www.teslamotorsclub.com/showthread.php/51563-Calling-P85D-owners-world-wide-for-survey-and-complaint-letter?p=1117782&viewfull=1#post1117782�
Oct 12, 2015
cynix 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.�
Oct 12, 2015
Luclyluciano 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.�
Oct 12, 2015
sorka 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.
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.
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Yup. I thought it was clear enough but apparently not.�
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