Letter To Elon Musk Regarding P85D Horsepower – Discussion Thread

[stopcrazypp]

I don't think so.

Here a P85D gets limited after one and a half minutes of aggressive driving:

That's with the battery attached however. The 3 minutes would be just the motors and inverters running at 80% power (never hitting 100% power).

Also I didn't notice this before, but the ECE R85 actually has all accessories disconnected (does not even match SAE net as I assumed, but is much closer to SAE gross):

2.3.2 Auxiliaries to be removed
The auxiliaries necessary for the proper operation of the vehicle, and which may be mounted on the motor shall be removed when performing the test.
The following non-exhaustive list is given as an example:
Air compressor for brakes; Power steering compressor; Suspension system compressor; Air conditioner system, etc.
Where accessories cannot be removed, the power they absorb in the unloaded condition may be determined and added to the measured power.

Another important line on page 42, which means the cooling can be run full blast the whole time (which may not necessarily happen on the car, where the drivetrain has to hit a certain temperature before thermostat is fully open):

The thermostat may be fixed in the fully open position.

http://www.unece.org/fileadmin/DAM/trans/main/wp29/wp29regs/2013/R085r1e.pdf


At any rate, Tesla's manual says they got those net power ratings based on ECE R85, which means they must have tested the motors at that power.

 

[vgrinshpun]

I don't think so.

Here a P85D gets limited after one and a half minutes of aggressive driving:

But I do not think this is the point.

The point is that the car was advertised as a 700 hp car and has less than 555 hp and even today there is still misleading information on the Tesla website:





Is this misleading advertising an accident? An oversight? Or is Tesla trying "to pull a Volkswagen"?

Is there any technical reason they can give combined hp for the 70D and 85D but not for the P85D?

I am not sure what a video showing P85D limited by the battery output has to do with presumably invalidating the ECE R85 test data for drivetrain obtained *without* considering the battery.

Regarding your question, first of all 70D and 85D does not show combined hp of the front and rear motor (which would be 259x2=518hp for both 70D and 85D), rather hp rating of the whole propulsion system, including drivetrain and the battery. The spec page shows both the motor power and the power rating for the whole propulsion system:

View attachment 95666

The technical reason for listing P85D motor horsepower, rather than the hp rating of the whole propulsion system, is that listing the latter would not be representative of the P85D ability to accelerate from 0 mph up to the speed at which the maximum battery output becomes the limiting factor, and therefore *misleading*. Ultimately, however, as pointed out in the JB Straubel's blog "The true measures for any performance EV driver are acceleration times and driving performance of the vehicle." The spec page lists both 0 to 60 mph and 1/4 mile acceleration times which uniquely identify performance of the P85D.

 

[Andyw2100]

Somehow I don't think they will go bankrupt and threaten the European economic union over this.

Fair point.

 

[stopcrazypp]

The point is that the car was advertised as a 700 hp car and has less than 555 hp and even today there is still misleading information on the Tesla website:

Is this misleading advertising an accident? An oversight? Or is Tesla trying "to pull a Volkswagen"?

Is there any technical reason they can give combined hp for the 70D and 85D but not for the P85D?

It's not technical, it is actually precisely in response to the 691 hp complaining on the P85D. If you rewind the clock back to October 2014 (P85D and dual motors launch) to March 2015 (before the 691hp complaining thread) the only power numbers listed were the "motor power" numbers including combined motor power numbers (the infamous 691hp).

Pre-6.2 update the 85D was rated 376hp motor power (188hp x2). The 70D/85D was rated at 514hp motor power (257hp x2). They have since removed the combined motor power numbers and added back system power (328hp for 70D, 417hp for 85D as your screenshot shows).
http://www.teslamotorsclub.com/show...91HP/page119?p=1115469&viewfull=1#post1115469

Tesla likely asked themselves a very simple question: If we post 550hp (or whatever the Ludicrous power is) for the P85D/P90D would this satisfy the people complaining about the 691hp rating on the P85D previously? The answer as we can see here is very obviously no. In fact, in might make matters worse. That is why they leave it out.

As I said, until Tesla gets P85D/P90D owners to understand how they arrived at their motor power ratings in general, they will not be adding a system power number back for the P85D/P90D.

 

[Alipapa]

It is funny, imagine you go to a restaurant and order a 12oz steak. When the waiter serve it to your table, you realize the steak is actually 8oz. You then complaint about it and the owner defend himself saying you as a customer misunderstood their weight numbering system. "12oz" means the steak was 12oz before it is was dry aged. He then educate you when it comes to steak, "size" doesn't matter. It is all about the taste and filling up your stomach.

 

[vgrinshpun]

It is funny, imagine you go to a restaurant and order a 12oz steak. When the waiter serve it to your table, you realize the steak is actually 8oz. You then complaint about it and the owner defend himself saying you as a customer misunderstood their weight numbering system. "12oz" means the steak was 12oz before it is was dry aged. He then educate you when it comes to steak, "size" doesn't matter. It is all about the taste and filling up your stomach.

Well, this "analogy" does not work. Weight of the steak uniquely identifies it's nutritional value (calories). One point on the power vs speed curve (and this is exactly what a power rating is), however, does not uniquely identify car's ability to accelerate.

The analogy might be perfect, though, in another sense. To paraphrase what stopcrazypp said, this massive confusing mess will not end until average person buying EV knows about EVs as much as they know about steaks...

 

[30seconds]

Somehow I don't think they will go bankrupt and threaten the European economic union over this.

Don't worry, the likelihood that Germany will let VW go bankrupt is infinitesimally small. This isn't Greece we are talking about.

 

[stopcrazypp]

It is funny, imagine you go to a restaurant and order a 12oz steak. When the waiter serve it to your table, you realize the steak is actually 8oz. You then complaint about it and the owner defend himself saying you as a customer misunderstood their weight numbering system. "12oz" means the steak was 12oz before it is was dry aged. He then educate you when it comes to steak, "size" doesn't matter. It is all about the taste and filling up your stomach.

Actually looking it up, restaurants typically give the precooked weight:

So what about that cut of red meat or burger you order in a restaurant? Menus typically refer to a raw weight, not the weight of the food served to you. This is based on an industry standard, not a regulation.

A hamburger described as a quarter of a pound (four ounces) will be about three ounces by the time you bite into it, and that eight-ounce filet will be about six ounces cooked.

https://www.washingtonpost.com/life...f5e2b4-89c0-11e3-916e-e01534b1e132_story.html
http://forum.bodybuilding.com/showthread.php?t=5410503

The actual weight you get when the water is out of the steak is significantly lower:
http://www.ontheregimen.com/2013/08/28/how-to-weigh-meat-cooked-or-raw/

So this is actually an example that supports Tesla's case! I see it very similar to a lot of people here claiming that publishing horsepower based on a standard that is not system power is false advertisement, but they miss that fact that there is an existing industry standard (ECE R85) that is not system power (and I have been saying, for the ICE case, SAE gross also is not system power).

 

[Andyw2100]

Actually looking it up, restaurants typically give the precooked weight:

As soon as I saw that example used, I knew someone would bring this up. It wasn't the best example to use.

So this is actually an example that supports Tesla's case! I see it very similar to a lot of people here claiming that publishing horsepower based on a standard that is not system power is false advertisement, but they miss that fact that there is an existing industry standard (ECE R85) that is not system power (and I have been saying, for the ICE case, SAE gross also is not system power).

Leaving aside for the moment the question of whether or not Tesla actually met all the requirements of the ECE R85 standard, let me bring up another point that no one has made yet.

Tesla used 1 foot rollout, which is common in the US, but not in Europe. They used it everywhere--all over the world--which has upset some people--in particular Europeans, as Europeans really had no reason to know anything about 1 foot rollout, etc.

Now Tesla is saying that at the same time that they were doing that, they were using a European standard--ECE R85--here in the US, and everywhere else to give the specifications for the power the car could produce. That's a standard that people in the US would have absolutely no reason to know anything about.

It seems to me Tesla can't have it both ways. It's completely disingenuous to cherry pick standards and practices from different parts of the world in order to make your car look as good as it possibly can. You could argue that the car is built in America, and thus was using American standards, and if the Europeans didn't know about 1-foot rollout, so be it. But you can't then follow up with, "Oh, and we used a European standard that Americans know nothing about to advertise the car's power capabilities in the United States and elsewhere."

Doing so makes no sense, unless the intent was to deceive.

(Note--it also makes sense if the original plan was to make the 691 HP legitimately, the company figured out that wasn't possible, and is now grasping at straws trying to cover their backsides.)

 

[darthy001]

As soon as I saw that example used, I knew someone would bring this up. It wasn't the best example to use.




Leaving aside for the moment the question of whether or not Tesla actually met all the requirements of the ECE R85 standard, let me bring up another point that no one has made yet.

Tesla used 1 foot rollout, which is common in the US, but not in Europe. They used it everywhere--all over the world--which has upset some people--in particular Europeans, as Europeans really had no reason to know anything about 1 foot rollout, etc.

Now Tesla is saying that at the same time that they were doing that, they were using a European standard here in the US. That's a standard that people in the US would have absolutely no reason to know anything about.

It seems to me Tesla can't have it both ways. It's completely disingenuous to cherry pick standards and practices from various countries, and use different ones from all over the world in order to make your car look as good as it possibly can. You could argue that the car is built in America, and thus was using American standards, and if the Europeans didn't know about 1-foot rollout, so be it. But you can't then follow up with, Oh, and we used a European standard that Americans know nothing about to advertise the car's power capabilities in the United States.

Doing so makes no sense, unless the intent was to deceive.

(Note--it also makes sense if the original plan was to make the 691 HP legitimately, the company figured out they couldn't, and now they are grasping at straws trying to cover their backsides.)

Some excellent points there that I hadnt thought of!

 

[vgrinshpun]

As soon as I saw that example used, I knew someone would bring this up. It wasn't the best example to use.




Leaving aside for the moment the question of whether or not Tesla actually met all the requirements of the ECE R85 standard, let me bring up another point that no one has made yet.

Tesla used 1 foot rollout, which is common in the US, but not in Europe. They used it everywhere--all over the world--which has upset some people--in particular Europeans, as Europeans really had no reason to know anything about 1 foot rollout, etc.

Now Tesla is saying that at the same time that they were doing that, they were using a European standard--ECE R85--here in the US, and everywhere else to give the specifications for the power the car could produce. That's a standard that people in the US would have absolutely no reason to know anything about.

It seems to me Tesla can't have it both ways. It's completely disingenuous to cherry pick standards and practices from different parts of the world in order to make your car look as good as it possibly can. You could argue that the car is built in America, and thus was using American standards, and if the Europeans didn't know about 1-foot rollout, so be it. But you can't then follow up with, "Oh, and we used a European standard that Americans know nothing about to advertise the car's power capabilities in the United States and elsewhere."

Doing so makes no sense, unless the intent was to deceive.

(Note--it also makes sense if the original plan was to make the 691 HP legitimately, the company figured out that wasn't possible, and is now grasping at straws trying to cover their backsides.)

How is Tesla cherry picking standards? If you know of any US standard or Regulation (yes, as always, you are avoiding inconvenient points, namely, that ECE R85 is a Regulation and compliance with it, therefore, mandatory) that deals with specifying power for an EV drivetrain, please share with us.

Aside from the fact that comparing selection of one of the **two** prevalent **practices** to specify acceleration to the use of **the only one** existing **Regulation** is, well, "completely disingenious" to borrow your words, the reason that Tesla used rollout for P85D most likely is quite innocent. I've posted about this about three weeks ago. Tesla's prominent claim for P85D was matching performance of the McLaren F1, which was 3.2s, with a rollout according to the MotorTrend. So in order to compare apples to apples they switched to the rollout adjusted time.

 

[dsm363]

If there is no US standard or regulation for EV drivetrains (there isn't) then Tesla could be accused of making up the numbers if they didn't follow something published (the EU regulations for example). But they are being accused of making it up anyway.

 

[rainman50]

From another post (hopefully someone will chime in and repost it), that he had a response directly from McLaren and they said the F1 spec was WITHOUT rollout.

I'll see if I can find that post again.

How is Tesla cherry picking standards? If you know of any US standard or Regulation (yes, as always, you are avoiding inconvenient points, namely, that ECE R85 is a Regulation and compliance with it, therefore, mandatory) that deals with specifying power for an EV drivetrain, please share with us.

Aside from the fact that comparing selection of one of the **two** prevalent **practices** to specify acceleration to the use of **the only one** existing **Regulation** is, well, "completely disingenious" to borrow your words, the reason that Tesla used rollout for P85D most likely is quite innocent. I've posted about this about three weeks ago. Tesla's prominent claim for P85D was matching performance of the McLaren F1, which was 3.2s, with a rollout according to the MotorTrend. So in order to compare apples to apples they switched to the rollout adjusted time.

 

[dsm363]

From another post (hopefully someone will chime in and repost it), that he had a response directly from McLaren and they said the F1 spec was WITHOUT rollout.

I'll see if I can find that post again.

But it appears Tesla went with what Motortrend was reporting. And since this is a car you basically can't find anymore to test easily seems reasonable as well.

 

[vgrinshpun]

From another post (hopefully someone will chime in and repost it), that he had a response directly from McLaren and they said the F1 spec was WITHOUT rollout.

I'll see if I can find that post again.

The response from McLaren did not include a direct answer. I asked them to comment on Motor Trend article that reported the 3.2s time for Mclaren F1 with a rollout. They just responded that "The F1 was recorded by Autocar magazine as doing 0-60 mph in 3.2 seconds from standstill, no rollout."

So what this boils down to, as I have already posted back three weeks ago, that the assumption that Tesla lied about matching performance of McLaren F1 is dead wrong based on facts that nobody cared to research before jumping to this conclusion. What we have is real test data from three magazines that tested the car back in the nineties, the British Autocar tested F1 at 3.2s, presumably without rollout (equivalent to 2.9s with a rolout), but in tests by two american magazines, both with rollout, F1 was significantly slower. In Aug 1994 Issue Car and Driver reportedtest time of 3.2s with rollout. In November 2012 article Road and Track reported that according to their 1997 test McLaren F1 achieved 3.4s with rollout. So in three documented tests F1 0 to 60mph acceleration time was 2.9s, 3.2s, 3.4 s (all with rollout or adjusted to be equivalent to a test with rollout). The bottom line is that Tesla claim that P85D, with 3.2s 0 to 60 time, based on data from two US car magazines, matches performance of McLaren F1, is completely legitimate, if not overly conservative.

 

[Canuck]

It's completely disingenuous to cherry pick standards and practices from different parts of the world in order to make your car look as good as it possibly can....Doing so makes no sense, unless the intent was to deceive.

Why? Even if Tesla was cherry picking standards, if I created a product I would market and sell it in the best possible light in order to make my product look as good as I possible could. That's not called deception, that's called capitalism.

 

[electrish]

Tesla Model S P85Ds Total Power Output Is Being Questioned by a Group of Owners - autoevolution

 

[vgrinshpun]

Tesla Model S P85Ds Total Power Output Is Being Questioned by a Group of Owners - autoevolution

"He's undoubtedly right, but you can't help feel Tesla took advantage of this confusion to post a very high horsepower figure. "

Of course the article does not mentioned that the main claim of the Owner's Letter the "missing horsepower" claim was made without the benefit of knowing the basic facts on the matter, the facts that are available for at least 6 months.

 

[Auzie]

Tesla Model S P85Ds Total Power Output Is Being Questioned by a Group of Owners - autoevolution

The comment sums it up:

 

[Andyw2100]

Why? Even if Tesla was cherry picking standards, if I created a product I would market and sell it in the best possible light in order to make my product look as good as I possible could. That's not called deception, that's called capitalism.

Is that really the kind of relationship you'd want to build with your customers? A relationship based on your having used standards you knew they would have no way of knowing about?

Personally I'd prefer to deal with a company that wanted me, as a customer, to have an accurate picture of the product I was going to purchase, as opposed to a company that was doing anything and everything they could to make the product look better than it actually was. Perhaps that's just me.