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Stop the Press! Tesla announces REAL HP numbers for P85D and P90L

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I think that you might be confused about *which* hp number defines the torque which produces acceleration. The formulas that you listed are correct, but in order to determine the torque which is constant for Tesla drive units in the lower part of rpms (starting from 0 rpm if one neglects transients) one needs to use *maximum motor hp rating* and rpm for that rating to calculate thedtiveunit torque. This torque is *not* dependent on the battery power limitation.

This is exactly the reason that including motors with the higher horsepower rating is beneficial, even if battery power limit is lower than horsepower rating of the motors.

You cannot calculate max torque of an electric motor from P and RPM. In motor used by Tesla 3 phase current is used to generate rotating magnetic field. This causes motor to turn, but there is a slip. Greater the slip is more torque motor produces.

Look at efficiency map from http://www.acpropulsion.com/datasheet/ac150gen2.pdf

Since power is torque*RPM*unit conversion blue line in efficiency map is set by max torque. It can be calculated from the map.
 
I see this issue, or the perception of it being an issue, as existing primarily in here, and even in here, amongst a very few.
If this issue has little support from P85D owners, it makes me wonder how much support a similar issue would have from P90DL owners if Tesla says "whoops" and revises the 10.9 sec 1/4 mile ET centerpiece of their $10K Ludicrous Speed Upgrade. Currently 11.4 sec seems to be what everyone is seeing (except Motor Trend). P90DL's are already achieving 2.8 sec 0-60 in the wild, so they will need a lot more HP from 60-120 to drop an 11.4 to an 10.9. My hunch is they will need more than the 532 HP that Tesla specs.
 
If this issue has little support from P85D owners, it makes me wonder how much support a similar issue would have from P90DL owners if Tesla says "whoops" and revises the 10.9 sec 1/4 mile ET centerpiece of their $10K Ludicrous Speed Upgrade. Currently 11.4 sec seems to be what everyone is seeing (except Motor Trend). P90DL's are already achieving 2.8 sec 0-60 in the wild, so they will need a lot more HP from 60-120 to drop an 11.4 to an 10.9. My hunch is they will need more than the 532 HP that Tesla specs.

This could be an actual issue. It is a performance metric, not performance extrapolated from a 'motor power' number that wasn't explained and wasn't understood at the time.
 
This could be an actual issue. It is a performance metric, not performance extrapolated from a 'motor power' number that wasn't explained and wasn't understood at the time.
Right. I've been arguing about the motor power thing, but the 1/4 mile is a straight forward spec that Tesla has to deliver. It would be their first instance of not delivering a specific performance spec.
 
.... Peak power is reached at 36 MPH ...

View attachment 100631

From your graph it looks like the peak, or a double-peak power point is closer to the 48 to 52 mph range, which is where the rear (5950 rpm) and front (6100 rpm) motors are specified to reach peak power.


The electric motor produces power that is proportional to the power fed it (voltage*current). The REST "power" log follows the power in this graph exactly, not the torque.

Right, REST power and torque are not the same thing, but motor output power is just a measured quantity of the amount of work that was done over a period of time. A motor generates torque based only upon current, and this torque provides the force of acceleration for the car, as also shown in your graph.

It would be great to have battery voltage and current measurements to plot on a graph along with the motor voltage and current, and your torque, speed and power data. Get the whole picture and calculate efficiencies.
 
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From your graph it looks like the peak, or a double-peak power point is closer to the 48 to 52 mph range, which is where the rear (5950 rpm) and front (6100 rpm) motors are specified to reach peak power.

Power is a measured quantity of the amount of work that can be done over a period of time
I say more like the ~45mph range. The other part looks like an anomaly. In this case, with a battery limited case is going to look very different than a case where the battery is not the limiter. I did an analysis here comparing P85D with P85+. The battery-limited P85D hits a power plateau, while the P85+ hits a peak and goes down gradually.

http://www.teslamotorsclub.com/show...91HP/page160?p=1210345&viewfull=1#post1210345
 
it says "Model S Performance" clearly. It is talking about just the P. This was clear to me when I looked at that page.

Tesla has a Model S and a Model X, there is no such thing as a Model P.

Seriously they bring this on themselves by using such confusing terminology that all the forum posts confuse it further.

Is the full name of the car "Model S P85D" or not? If so then "Model S performance" applies to all varieties P or not, D or not.
 
Tesla has a Model S and a Model X, there is no such thing as a Model P.

Seriously they bring this on themselves by using such confusing terminology that all the forum posts confuse it further.

Is the full name of the car "Model S P85D" or not? If so then "Model S performance" applies to all varieties P or not, D or not.

All performance cars now are Ds.
 
You make several very good points about people who are not owners. You may also say that owners are hypercritical, but I feel that this is justified, since they had immense expectations based on how Tesla presented the car.
Don't get me wrong, I am very happy with my car and would not return it based on lemon laws or anything else. However, I think it falls short of my expectations on several performance marks, and I am not even a race car driver.

The car was not presented initially, when it couldn't be test driven, as it is today. Do I believe that Tesla intentionally quoted numbers that were not based on actual performance? No, I believe they expected to significantly improve performance with OTA updates and they were successful in doing so for the 85D, but ran into technical issues with the P85D. They stated performance would dramatically improve at highway speeds. Why else would they come out with a marginal battery improvement within a year of the D event, when they stated "No new upgrades to the platform for another year!" The P90DL is probably what they envisioned the P85DL to be (minus he bigger battery). But I don't think it's ok to now charge for his upgrade. At least that's my opinion.

And I appreciate your having expressed it.

One thing is certain, and that is time will prove some of us right and some of us wrong.

My prime focus, is on whether or not this whole "horsepower" discussion, is likely to have any significant, or more importantly "damaging", impact on Tesla's reputation, outside of this particular community, a community which is of small number.

I see nothing to indicate that it will. Nor, in my opinion, should it.

But as I said earlier, I've seen nothing, anywhere, which would indicate that this matter and it's discussion are going to go much further than here.

I'll demonstrate what I mean in my response to Andy's post below.

...<snip>
I have stated the following before, but you conveniently choose to ignore it because it better suits the argument you are trying to make.

There is no doubt that the letter could have had far more signatures than it did. I started gathering signatures on a Thursday, without linking the thread to many of the threads I planned to link it to. I planned to wait a day or two, until there were a fair number of people expressing support, and then link the thread to some of the other threads where people had been discussing the related issues, and also link it to the original P85D ordering thread. When the letter was picked up by the "Learn Bonds" site, which happened the next day, I decided that I should try to maintain as low a profile as possible on the letter, since it was never my intention for word of it to get out beyond TMC and Elon Musk / Tesla. So I never publicized the letter or my attempt to get signatures the way I would have. I also closed the acceptance of signatures after just one week, so that the letter could be sent off.

So while you can keep using the fact that there were only about seventy signers to attempt to indicate a lack of interest, that's just not an accurate reflection of reality.

To the part in red above, it is difficult for me to imagine how one would not have the foresight to conclude that such a sensationalistic thread, complete with a letter meant for the CEO, would not potentially attract those with their own agenda, and provide "accelerant" to others who may not necessarily want to see Tesla succeed.

But anyway, a link to the Learn Bonds article is below.

Tesla Motors Inc (TSLA) Lied About Model S, now Fans Are Revolting

I don't get the impression that an awful lot of thought went into the possible down side of such a thread and effort as the one being referred to in that article.

However, at this point, it's all water under the bridge. What's done is done.

That said though, in light of the discussion on the horsepower and that letter managing to find it's way onto the "wrong ears", even though the Learn Bonds site got ahold of it, and attempted to run with it, the subject matter still never took off. Never made the front page or the cover of any notable main stream periodicals, at least not in these United States. Tesla has come through it apparently unscathed. Nobody grabbed this story and ran with it. Won't touch it. ....... And you have to ask yourself; "why not?" And when you do, what is your answer. I know what mine is.

That Learn Bonds site blared this as loudly as it could, and well, nothing. No apparent ill effects. P85D and P90Ds are still selling, and I've yet to see anything about this on the CBS Evening News.

This is part of why I'm not overly concerned that this matter will make it much further than what it has.

This matter reminds me a lot of the Obama birth certificate incident.

Started at the "grass roots" level. Had all the promise in the world, or so some thought, of becoming a "hot button issue", and an issue which would reach the mainstream. Those who brought it up, could swear that they were on to something. People who believed that it was an issue, held onto that belief.

Mainstream media, would not touch it. Many who were harping on it, weren't really taken seriously then, let alone now.

Very similar, but instead of hollering "where's the horsepower?", they were yelling "where's the birth certificate?"

Of course now, and really for a long time prior to now, anyone bringing it up, the "birth certificate" that is, is looked at in well, let us say, less than a serious light, and it is my belief that anyone bringing this matter up 5-6 years from now, will be looked at in a similar light, and taken just as seriously.
 
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Coming back to this this thread I notice a slight harmonization (perhaps less noticeable to those deeply entrenched on either "side"):

The 691 "motor hp" rating is important as it explains the difference in torque hence 0-40 mph improvement over 4xx hp motors.

Now it would seem the issue has somewhat shifted toward somethings that could be summed up as "my alleged 691 hp car does not perform as expected from a true 691 hp EV [with a power supply capable of providing 691 hp throughout the RPM range of operation] after 30/40 mph" issue.

My personal opinion, mind you having not personally spent the money buying a P85/90D, is that those who feel cheated are partly entitled to their disappointment but also partly themselves to blame for not having done their due diligence. Tesla, again IMO, are likely more guilty of poor/insufficient communication rather than lying/deceitful behavior.
 
Perhaps the now discounted ludicrous upgrade is that, I don't know. But it's certainly less than half the cost of what new owners are paying for it.

No, it's not.

The upgrade when purchasing a new car costs $10,000. When announced, the upgrade for P85D owners was to be $5000 plus labor costs. Later it was offered on the website for $7500. Since then that price has been lowered to $5000, so if that is the complete price, and Tesla sticks with it, the price will be exactly half the cost of what new owners are paying for it, but not "certainly less than half."



That said though, in light of the discussion on the horsepower and that letter managing to find it's way onto the "wrong ears", even though the Learn Bonds site got ahold of it, and attempted to run with it, the subject matter still never took off. Never made the front page or the cover of any notable main stream periodicals, at least not in these United States. Tesla has come through it apparently unscathed. Nobody grabbed this story and ran with it. Won't touch it. ....... And you have to ask yourself why not. And when you do, what is your answer. I know what mine is.

I'll tell you my answer.

It's that the P85D owners who are affected by this are still willing to give Tesla the benefit of the doubt, and are expecting Tesla to make things right. We're exhibiting patience because we don't want to see Tesla hurt. But I expect our collective patience is running out, as evidenced by what's going on in Denmark and Norway. When our patience does eventually run out, if and when we make a concerted effort to actually try to get news of this out to all P85D owners, and to the general public, I assure you the mainstream media will pick up on it. I don't think I'll be the one leading that charge, because I'm not interested in seeing Tesla hurt, but someone will lead it, and it will not be a difficult fight to lead.
 
No, it's not.

The upgrade when purchasing a new car costs $10,000. When announced, the upgrade for P85D owners was to be $5000 plus labor costs. Later it was offered on the website for $7500. Since then that price has been lowered to $5000, so if that is the complete price, and Tesla sticks with it, the price will be exactly half the cost of what new owners are paying for it, but not "certainly less than half."

It costs $13,000 to get ludicrous mode in a new car. So sure you get a little bit more range but it's not a huge amount.
 
It costs $13,000 to get ludicrous mode in a new car. So sure you get a little bit more range but it's not a huge amount.

You can get a 90 pack or an 85 pack, and the difference between those two is $3,000. If you get the 90 pack you can get Ludicrous or you can not get Ludicrous. If you choose to get it, the cost is $10,000. The fact that you can't get Ludicrous with an 85 pack is not relevant.
 
You can get a 90 pack or an 85 pack, and the difference between those two is $3,000. If you get the 90 pack you can get Ludicrous or you can not get Ludicrous. If you choose to get it, the cost is $10,000. The fact that you can't get Ludicrous with an 85 pack is not relevant.

It is totally relevant, since you can't have ludicrous mode without paying $13,000 over the base P85D. Therefore, that's what it costs. It costs an existing P85D owner $5000 at this point (leave the arguing about final performance for another day)
 
I say more like the ~45mph range. The other part looks like an anomaly. In this case, with a battery limited case is going to look very different than a case where the battery is not the limiter. I did an analysis here comparing P85D with P85+. The battery-limited P85D hits a power plateau, while the P85+ hits a peak and goes down gradually.

http://www.teslamotorsclub.com/show...91HP/page160?p=1210345&viewfull=1#post1210345

There's some random variation from one run to another I agree that it's closer to the mid 40s for actual peak even if it's 95% by the mid 30's:

p85d65P.jpg


And compared to a P85+:

P8590SOC.jpg
 
It is totally relevant, since you can't have ludicrous mode without paying $13,000 over the base P85D. Therefore, that's what it costs. It costs an existing P85D owner $5000 at this point (leave the arguing about final performance for another day)

You are also getting a bigger battery for $13,000.

Someone already buying a 90 can choose to buy Ludicrous for $10,000 or not buy Ludicrous for $10,000. That is the cost of Ludicrous. $13,000 gets you Ludicrous and a bigger battery. $13,000 is not the cost of Ludicrous.