P85D and P90D horsepower disagreement

[LetsGoFast]

I've actually come around somewhat to sorka's position because the ludicrous mode announcement has changed the facts somewhat. Previously, they claimed 691 hp and my argument was that this represented purely the rated horsepower of the electric motors, independant of the power applied. I don't think it is the most accurate way to represent the hp of the car, but they always were careful to call it "motor power" and I was willing to cut them a break. However, with the new announcement they now claim the car has 762 hp. This clearly suggests that they are using the total output of the engine as a system and I think the REST data conclusively demonstrates that the engines don't even consume that much electricity. At the present time, I cannot come up with a technical justification for the hp figures being quoted. I still love my car, I'm never looking to sue anyone or even to complain on the forum -- but I have changed my mind from believing that Tesla had a clear technical justification for using the hp figure that they use to no longer believing it is accurate.

To be honest, I don't see how the upgrade "fixes" anything. I suppose the car may now deliver something more like 691 horsepower, but it is now rated at 762, so the problem just shifted to the right. Perhaps some people have the actual complaint that the car just isn't fast enough to suit them from 40-70 and now they will find the performance meets their standards.

 

[Johan]

It's just like the battery: "85 kWh". Except no-one was ever able to extract 85000 Wh from it driving the car. And so what? Range (EPA, at constant 65 mph or whatever metric) is what matters.

 

[dsm363]

People wouldn't have a case. While highly misleading Tesla always said 'motor power' as you said. They shouldn't be doing that but as long as Tesla hit their advertised 0-60 mph time that's all that matters to them. Did they lie about the 1/4 mile time? Don't think so. How about the 40-70mph speed as you said? No to that as well.

Yes it's disappointing I'm sure but talk of getting lawyers involved is way over the top. It's the reason why so many things cost so much in the U.S. and most companies just shut up and don't talk about their products.

 

[gordo]

I've actually come around somewhat to sorka's position because the ludicrous mode announcement has changed the facts somewhat. Previously, they claimed 691 hp and my argument was that this represented purely the rated horsepower of the electric motors, independant of the power applied. I don't think it is the most accurate way to represent the hp of the car, but they always were careful to call it "motor power" and I was willing to cut them a break. However, with the new announcement they now claim the car has 762 hp.

No they don't. Go to Design Studio and look at P85D: 259hp front, 503hp rear "motor power". In other words, each motor is capable of those numbers independently, but they're no longer adding these numbers together as they used to. This is really the core beef I had with the whole thing from the start. When you add the front and rear together, you get a number (691 previously, 762 going forward) that's above what the car is capable of delivering simultaneously (due to whatever limitations: pack discharge rate, fuses, contactors, etc.)

If they'd actually presented P85D this way from the beginning, I think a large part of the fiasco could have been avoided.

 

[Sad]

If they'd actually presented P85D this way from the beginning, I think a large part of the fiasco could have been avoided.

+1. Ideally of course they should just put the expected peak HP like they do for the other models. And in a perfect world, under which conditions (e.g. RPM or speed range) it is achievable, like they used to. But maybe it's pure marketing genius from Tesla, as every journalist emphasized that 691 number in their review, and none of them challenged it.

 

[sorka]

I think Tesla is in the clear on the new rating because they're not actually listing a combined hp rating anywhere. But previously they said "691 hp" before motor power. hp still means horsepower and it still means 746 watts / hp. Saying "motor power" specifies that the hp is at the motor which is equivalent to manufacturers of ICE cars specifying hp at the motor crankshaft. Really, I don't see how this is any difference and I don't think the general public when they read 691 hp is going to expect it to be any different or wonder if it should be. If Tesla had meant something other than actual hp, they should have said so and if they didn't, then it's clearly misleading intentionally. I don't think Tesla is intentionally misleading anyone. I think they ran into an honest to goodness problem and couldn't deliver what they had good intentions to do so.

But note, Tesla has not ONCE come out and said they didn't mean hp when they said hp. Not once. This crazy hairball word game that others using to try and justify it is not Tesla's doing. They have nothing to do with it. They've simply removed the combined rating. My personal speculation, is that they fully intended to meet the goal but discovered in the end that they couldn't run the fuse at a close enough tolerance to reliably keep it from blowing if they were to extra 515 KW from the battery.

So in order to meet the original goal, they had to change some hardware. But not the motors or battery. The motors aren't capable of any more hp than they were before. They were capable of much more but only when fed enough to achieve more.

 

[stopcrazypp]

I think Tesla is in the clear on the new rating because they're not actually listing a combined hp rating anywhere. But previously they said "691 hp" before motor power. hp still means horsepower and it still means 746 watts / hp. Saying "motor power" specifies that the hp is at the motor which is equivalent to manufacturers of ICE cars specifying hp at the motor crankshaft. Really, I don't see how this is any difference and I don't think the general public when they read 691 hp is going to expect it to be any different or wonder if it should be. If Tesla had meant something other than actual hp, they should have said so and if they didn't, then it's clearly misleading intentionally. I don't think Tesla is intentionally misleading anyone. I think they ran into an honest to goodness problem and couldn't deliver what they had good intentions to do so.

But note, Tesla has not ONCE come out and said they didn't mean hp when they said hp. Not once. This crazy hairball word game that others using to try and justify it is not Tesla's doing. They have nothing to do with it. They've simply removed the combined rating. My personal speculation, is that they fully intended to meet the goal but discovered in the end that they couldn't run the fuse at a close enough tolerance to reliably keep it from blowing if they were to extra 515 KW from the battery.

So in order to meet the original goal, they had to change some hardware. But not the motors or battery. The motors aren't capable of any more hp than they were before. They were capable of much more but only when fed enough to achieve more.

HP is simply a unit, like kW. It doesn't imply that it is somehow tied to the car as a whole as you are trying to say (aka motor crank shaft). How else do you suggest they advertise the motors lone capability (as we know they were doing back then)? If they said "691 motor power" that does not make sense because of lack of units.

I'll refer you here to this again on what they meant when they put "motor power".
http://www.teslamotorsclub.com/show...eement/page4?p=1076026&viewfull=1#post1076026

What they mean is that if that the motors can support that much power output, so if they ever upgrade the other components that is what the motor would be capable of (as they are doing now with the P90D). Basically the same as if you were buying a motor completely separately from the car. I used the S60 as an example because it is not mixed in with the complications of dual motors. It was rated at 380 hp (283kW) "motor power". The 60kWh pack is never able to put out that much power (it put out 225kW). However, there had been one person who upgraded their pack to the 85kWh and then they got the "motor power".

Again, you can say this type of advertising is misleading, but that is how they advertised it.

 

[sorka]

HP is simply a unit, like kW. It doesn't imply that it is somehow tied to the car as a whole as you are trying to say (aka motor crank shaft). How else do you suggest they advertise the motors lone capability (as we know they were doing back then)? If they said "691 motor power" that does not make sense because of lack of units.

I'll refer you here to this again on what they meant when they put "motor power".
http://www.teslamotorsclub.com/show...eement/page4?p=1076026&viewfull=1#post1076026

What they mean is that if that the motors can support that much power output, so if they ever upgrade the other components that is what the motor would be capable of (as they are doing now with the P90D). Basically the same as if you were buying a motor completely separately from the car. I used the S60 as an example because it is not mixed in with the complications of dual motors. It was rated at 380 hp (283kW) "motor power". The 60kWh pack is never able to put out that much power (it put out 225kW). However, there had been one person who upgraded their pack to the 85kWh and then they got the "motor power".

Again, you can say this type of advertising is misleading, but that is how they advertised it.

Um, no. Tesla never said that. You may interpret it that way but they didn't say that. If they did, *that* would be intentionally misleading and I don't think Tesla ever intended to mislead anyone.

No other manufacturer has ever specified power by what their ICE could deliver with different inputs. They specify what it actually produces with the the power train components that are attached to the engine.

Many many ICE cars can have their power increased, sometimes drastically, with just a software change, but those manufactures don't specify hp by what their cars could be making if you changed their software or modified them in some other way.

The P85D delivers a 414KW maximum at 100% SOC. There are no scenarios where this can result in more than 555 hp. There are lots of different ways to measure power. Brake dynos measure engines at static speeds on a static load with all equipment attached. If you add a flywheel to this setup, the hp measure will remain the same. If you use a Dynojet to measure hp, changing to a lightened flywheel will result in measuring more power without changing static power. But under all possible methods of measuring power, there is no method that can measure more power than X power when only x = Y KW / 746 is provided.


Remember, Tesla has used the "motor power" terminology on other Teslas that actually make that power

Model S | Tesla Motors

S85 = "380 hp motor power"
P85D = "691 hp motor power"

The S85 makes 375 at the wheels. More than they actually claim.
There's only a 120 hp at the wheels difference between the P85D and the S85. Yet look at the difference in their spec using the same terminology for both. WAY bigger difference. 691 minus 380.

 

[stopcrazypp]

Um, no. Tesla never said that. You may interpret it that way but they didn't say that. If they did, *that* would be intentionally misleading and I don't think Tesla ever intended to mislead anyone.

You are once again ignoring my S60 example, which succinctly shows my point. I put it out here again.

How do you explain how the S60 went from 302 hp to 380 hp "motor power" (same as a S85) and then back to 302hp (and recently 315hp for the S70).

There is no other way to explain that other than my explanation. And to make it clear even if what I am saying is true, that does not mean Tesla was intentionally trying to mislead. They may have thought that was a good metric to advertise if they were planning on allowing pack upgrades in the future for existing drivers (as they are doing for the 85kWh to 90kWh). They quickly removed it after people complained it was misleading.

 

[3mp_kwh]

Sorka,


I think you ask too much, with top end expectations given the "691HP", but then too little when you write:

Saying "motor power" specifies that the hp is at the motor which is equivalent to manufacturers of ICE cars specifying hp at the motor crankshaft. Really, I don't see how this is any difference and I don't think the general public when they read 691 hp is going to expect it to be any different

The not too small difference, here, is that the ICE "at the crank" claim is a number that is delivered >99% of the time, when an OEM represents it this way. And these companies aren't targeting the "general public", like John Oliver on the street. They are accepting money from buyers of performance cars. When that type of person reads a HP rating, they reasonably expect what they're buying will produce it. Am I way off base, here? Am I to apply a Tesla filter, for what they "meant". Just because people don't appreciate torque, etc., is no reason to lie about peak HP or to get into the nonsense of capacities that won't be taken advantage of in the product.

"259 hp front, 503 hp rear motor power"
I dunno, maybe add:
*Battery hardware not included
**259 hp and 503 hp not included
***Almost, but not responsible for 85kwh impacts
****You turn the wheel, we choose the power

All fair qualifiers, IMO. All fixable. Otherwise, misleading.

 

[brianman]

How do you explain how the S60 went from 302 hp to 380 hp "motor power" (same as a S85) and then back to 302hp (and recently 315hp for the S70).

There is no other way to explain that other than my explanation.

There are multiple ways to explain it. Some easy ones off the top...

1. An obvious one is web content or web design fail; unfortunately, we see that sometimes with the teslamotors.com site.
2. Call it "evolving understanding" of the capabilities of the motor -- and updating the site to reflect the current understanding.
3. Maybe there are 2 (or more) versions of the motor in the S60. Maybe the first one was confidently rated at 302 and they discovered it could handle more (after testing) so they bumped up the rating; or maybe they refined the design and/or manufacturing which allowed for a higher rating. For either of those cases, they may have discovered a cost-saving, manufacturing speed, safety, or reliability reason to set the rating back to 302 for the latest ones off the line.

 

[sorka]

You are once again ignoring my S60 example, which succinctly shows my point. I put it out here again.

How do you explain how the S60 went from 302 hp to 380 hp "motor power" (same as a S85) and then back to 302hp (and recently 315hp for the S70).

There is no other way to explain that other than my explanation. And to make it clear even if what I am saying is true, that does not mean Tesla was intentionally trying to mislead. They may have thought that was a good metric to advertise if they were planning on allowing pack upgrades in the future for existing drivers (as they are doing for the 85kWh to 90kWh). They quickly removed it after people complained it was misleading.

I've never seen a dyno an S60. But if they changed it from 302, which is likely what it was given its current performance, to 380, and then back down, I'd say that was an error and they caught it and fixed it. Anyone who bought an S60 during that period would have a legitimate beef as well.

 

[stopcrazypp]

There are multiple ways to explain it. Some easy ones off the top...

1. An obvious one is web content or web design fail; unfortunately, we see that sometimes with the teslamotors.com site.
2. Call it "evolving understanding" of the capabilities of the motor -- and updating the site to reflect the current understanding.
3. Maybe there are 2 (or more) versions of the motor in the S60. Maybe the first one was confidently rated at 302 and they discovered it could handle more (after testing) so they bumped up the rating; or maybe they refined the design and/or manufacturing which allowed for a higher rating. For either of those cases, they may have discovered a cost-saving, manufacturing speed, safety, or reliability reason to set the rating back to 302 for the latest ones off the line.

I've never seen a dyno an S60. But if they changed it from 302, which is likely what it was given its current performance, to 380, and then back down, I'd say that was an error and they caught it and fixed it. Anyone who bought an S60 during that period would have a legitimate beef as well.

I would buy that explanation if the S60 was the only car affected and they didn't deliberately add "motor power" (which never existed on the website previously) to their wording.

However, they put "motor power" ratings for every single version of the Model S at the time, all of which were higher than previously and all of which were later decreased when they removed the "motor power" wording.

For the S85D they actually had two ratings at once in the European sites: a 422hp rating and a separate 522 "motor power" rating (261 front + 261 rear).

It was clear at the time that there was no hardware change in the motors. We knew from the start that the S60 and S85 used the same motor. The only reason why the power ratings were different between the two models was because of the battery (lower voltage for 60kWh pack). They changed that with the "motor power" metric.

See how they rated the S60 vs S85 (both 380hp "motor power") and S60D vs S85D (both 188 F + 188 R = 376hp "motor power"). There is no way to explain that other than that "motor power" represents only the power of the motor regardless of battery limitations.
http://www.teslamotorsclub.com/show...eement/page4?p=1076026&viewfull=1#post1076026

 

[brianman]

For the S85D they actually had two ratings at once in the European sites: a 422hp rating and a separate 522 "motor power" rating (261 front + 261 rear).

Why was this only on the European sites? Are the disclosure standards different for Europe than for the U.S.? Or something else.

 

[sorka]

I would buy that explanation if the S60 was the only car affected and they didn't deliberately add "motor power" (which never existed on the website previously) to their wording.

However, they put "motor power" ratings for every single version of the Model S at the time, all of which were higher than previously and all of which were later decreased when they removed the "motor power" wording.

For the S85D they actually had two ratings at once in the European sites: a 422hp rating and a separate 522 "motor power" rating (261 front + 261 rear).

It was clear at the time that there was no hardware change in the motors. We knew from the start that the S60 and S85 used the same motor. The only reason why the power ratings were different between the two models was because of the battery (lower voltage for 60kWh pack). They changed that with the "motor power" metric.

See how they rated the S60 vs S85 (both 380hp "motor power") and S60D vs S85D (both 188 F + 188 R = 376hp "motor power"). There is no way to explain that other than that "motor power" represents only the power of the motor regardless of battery limitations.
http://www.teslamotorsclub.com/show...eement/page4?p=1076026&viewfull=1#post1076026

Except that the S85 with the 380 hp motor power rating actually makes even more than that at the motors since makes 375 at the wheels. There's no way around that. That's a fact. The way around the inconsistencies you mention are simply errors in listing. If someone bought an S60 when it said 380 hp, and if it doesn't, and I haven't seen an example or any data all on the S60, then those people would have a legitimate beef as well.

There's no getting around the fact that when they were advertising 380 on the S85 vs 691 on the P85D using the same terms that relative to each other, there was a massive irreconcilable difference. The problem is that when a manufacturer understates the hp rating, like they did on the S85, they don't get in trouble. When they massively overstate the hp rating on the other hand, that usually has consequences.

Did they make a mistake using the 691 number in the rating? Maybe, but it was there for a long time and they're on the hook for that especially since every magazine and car publication that published the hp spec for the P85D never retracted it or changed it. If it was a mistake, Tesla should have informed all the publications at least and anyone who'd already placed an order.

The P85D doesn't make 691 hp with any system of measurement you could come up with. There's no way around that. You can play all the word games you want and that will never change.

 

[brianman]

The P85D doesn't make 691 hp with any system of measurement you could come up with. There's no way around that. You can play all the word games you want and that will never change.

This part I disagree with you. The optimist in me hopes that Tesla will make this right at some point while I still have a driver's license.

 

[stopcrazypp]

Why was this only on the European sites? Are the disclosure standards different for Europe than for the U.S.? Or something else.

No idea why. It still has both ratings if you look at the Swedish site (except like the P85D they removed the reference to the combined 522 hp number, and only have 262 F + 262 R).
http://www.teslamotors.com/sv_SE/models

Reference to previous numbers here:
http://www.teslamotorsclub.com/show...aded-85D/page2?p=967457&viewfull=1#post967457

 

[brianman]

Thanks, stop.

http://www.teslamotors.com/sv_SE/models

It's definitely suspicious and odd that the top-of-the-line offering omits a metric that every other offering lists. It's all but admitting that Tesla is hiding something.

 

[sorka]

This part I disagree with you. The optimist in me hopes that Tesla will make this right at some point while I still have a driver's license.

+1. I hope they make it right too. It could be that the discount on the L upgrade is how they intend to do this. There's no way they would have offered this on existing cars had they not been aware of this burning issue being debated endlessly day and night

 

[stopcrazypp]

The P85D doesn't make 691 hp with any system of measurement you could come up with. There's no way around that. You can play all the word games you want and that will never change.

I never claimed the car did make 691hp (in regards to the car today right now as it is with no modifications or updates). I only claimed you were misinterpreting what they mean with the "motor power" rating. My point was that the wording they used only promised the motors are capable of 691hp. If the "ludicrous" update enables 691hp at the wheels or crank with no change to the motors, then that proves they were not lying about their claim.

However, that actually isn't really required. We know the "470hp" claim for the rear motor is plausible given 430whp measured for the P85. We don't have independent tests of the front motor being "221hp", but the S85D has the power meter go to ~320kW (429hp), which splits out to 215hp. So both motor ratings are plausible.

Of course, you can say the wording was misleading (and I think Tesla agreed, which was why they removed it), but again my argument is over what they really meant with that wording.

- - - Updated - - -

+1. I hope they make it right too. It could be that the discount on the L upgrade is how they intend to do this. There's no way they would have offered this on existing cars had they not been aware of this burning issue being debated endlessly day and night

I agree with this. They probably realize the "691 hp motor power" was misleading (they admitted as much by removing that number), which is what the discount for the ludicrous update is mainly supposed to address. My guess is that Tesla probably did intend to deliver something closer to the "motor power" (as they did with the P85 and S85) with an update, but ran into the fuse issue. It's still possible that there is another update to squeeze a bit more out, but given the ludicrous announcement that probability is quite low.