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

[jerry33]

Shouldn't we have clear and unambiguous statements from Tesla?

Wouldn't that cut out about 80% of the posts on TMC? We'd be bored silly.

 

[tomas]

This group would find a way to dispute and argue over the clearest, most unambiguous statement.

 

[vgrinshpun]

Yep, this is exactly why the ECE R85 standard is so absurd. This standard does not benefit consumers at all.

stopcrazypp, you say that current standards for measuring engine/motor power all dictate that you take the engine/motor and attach accessories as appropriate. Whilst the gist is correct, the difference is that SAE actually requires you to attach the accessories that have an effect on engine performance, whereas ECE R85 discards a very crucial "accessory" — the battery — which is typically the limiting factor in an EV due to current technological constraints. And before you bring up your examples of manufacturers still using SAE gross hp today, I'd like to point out that, out of the thousands of car models on the market, only a couple of manufacturers and several non-mainstream models are still using SAE gross hp. I think this clearly shows that the majority of people expect to see SAE net hp these days.

How do you think the ECE R85 should be modified to "benefit consumers"?

 

[kennybobby]

Agree on all accounts. The main issue is there isn't an SAE standard for EVs yet.

Yes but there is IEEE 112, IEEE Standard Test Procedure for Polyphase Induction Motors and Generators, which would be used by most of the electrical engineers who deal with AC induction motors. i'll bet there is a copy of it at TMC too.

In addition it has instructions for measuring bearing currents as well as performance measurements.

 

[cynix]

How do you think the ECE R85 should be modified to "benefit consumers"?

By requiring manufacturers to use a rating that can actually be achieved by the car they're selling.

 

[vgrinshpun]

By requiring manufacturers to use a rating that can actually be achieved by the car they're selling.

And what that rating for the original P85D would be?

 

[cynix]

Yes but there is IEEE 112, IEEE Standard Test Procedure for Polyphase Induction Motors and Generators, which would be used by most of the electrical engineers who deal with AC induction motors. i'll bet there is a copy of it at TMC too.

I'm not an electrical engineer and I have no idea what that standard says. But we're buying cars, not motors, so I would expect to see a rating for the car as a whole. I wouldn't mind to also see a rating under that standard I guess, the more information the better.

 

[cynix]

And what that rating for the original P85D would be?

That would appear to be 463 hp, according to Tesla's latest specs.

 

[vgrinshpun]

Yes but there is IEEE 112, IEEE Standard Test Procedure for Polyphase Induction Motors and Generators, which would be used by most of the electrical engineers who deal with AC induction motors. i'll bet there is a copy of it at TMC too.

In addition it has instructions for measuring bearing currents as well as performance measurements.

I hope you understand that Tesla drivetrain power/torque curve has nothing in common with the curves of induction motors.

 

[Canuck]

This group would find a way to dispute and argue over the clearest, most unambiguous statement.

I disagree!

 

[tomas]

Yeah! Me too,,, uh, wait a sec :redface:

 

[vgrinshpun]

That would appear to be 463 hp, according to Tesla's latest specs.

Listing this number (463) alone will not explain the phenomenally good 0 to 60 acceleration numbers, and therefore, will not be entirely useful for the consumers, as you put it.

The point that I made many times is that the fact that both the torque and power curves at lower rpms, starting from 0 are actually straight lines and therefore motor power and torque are proportional, means that the motor power rating, when specified at given rpm is uniquely identifies motor torque, which is for Tesla drivetrain defines how quickly the power can be ramped up from the stand still.

So listing 463hp without 691 motor hp will not accurately describe the P85D and will di disservice to consumers because it will not allow them to compare P85D to other (ICE) cars in a meaningfull way. As I said more than once, I am all for listing both numbers, but the problem is that there is so much technical information behind them that they are meaningless for anybody who is not intimately familiar with the technical background. This is unfortunate part that everybody on your side of the discussion just not willing to consider/recognize. Looking for one number, similar to an ICE car, just does not work for an EV. There is no way square peg will fit round hole.

 

[dsm363]

Yes but there is IEEE 112, IEEE Standard Test Procedure for Polyphase Induction Motors and Generators, which would be used by most of the electrical engineers who deal with AC induction motors. i'll bet there is a copy of it at TMC too.

In addition it has instructions for measuring bearing currents as well as performance measurements.

This addresses electric motors as part of a vehicle and measures hp at shaft?

 

[cynix]

Listing this number (463) alone will not explain the phenomenally good 0 to 60 acceleration numbers, and therefore, will not be entirely useful for the consumers, as you put it.

But they already list the 0-60 number, which is a much better indication of… the phenomenally good 0-60 performance. When I look at the hp number, I'm not trying to translate it into 0-60 performance (since that's already known), I'd be using it as an indication of something that isn't already listed, such as performance at high speed.

I'm happy to see both 691 and 463 listed. Like I said, the more information the better. But if they had to list a single number for some reason, I'd prefer it to be a number that can be achieved in the car. If nothing else, I think it's better to list 463 and let the customer (who is not intimately familiar with the performance characteristics of an EV) be pleasantly surprised by the superior performance at low speeds, rather than listing 691 and let the same customer be disappointed by the mediocre performance at high speeds.

 

[tomas]

@ what RPM should they list the number? As I recall, ICE HP and Torque curves peak at specific (different) RPMs. Not trying to enter the fray, but just curious who thinks what.

 

[vgrinshpun]

But they already list the 0-60 number, which is a much better indication of… the phenomenally good 0-60 performance. When I look at the hp number, I'm not trying to translate it into 0-60 performance (since that's already known), I'd be using it as an indication of something that isn't already listed, such as performance at high speed.

I'm happy to see both 691 and 463 listed. Like I said, the more information the better. But if they had to list a single number for some reason, I'd prefer it to be a number that can be achieved in the car. If nothing else, I think it's better to list 463 and let the customer (who is not intimately familiar with the performance characteristics of an EV) be pleasantly surprised by the superior performance at low speeds, rather than listing 691 and let the same customer be disappointed by the mediocre performance at high speeds.

The problem is that consumers are conditioned to look at hp numbers to compare the cars and decide just how much they are worth, and this is reality regardless of any other metrics listed by manufacturers, including acceleration. This is just the automotive world reality that everybody, including Tesla, must live with.

The problem with listing only 463hp is that it eliminates any distinction between the 691 motor hp, 463 hp car and 463 motor hp, 463hp car. The first one will perform as P85D, the second will perform worth than 85D. There is no way the car can be properly marketed using 463hp only. There will be no consumers to be pleasantly surprised because nobody will buy 691 motor hp , 463 hp car over the 463 motor hp, 463 hp car if both are listed as 463hp cars, and the first car costs more.

 

[bonnie]

The problem is that consumers are conditioned to look at hp numbers to compare the cars and decide just how much they are worth, and this is reality regardless of any other metrics listed by manufacturers, including acceleration. This is just the automotive world reality that everybody, including Tesla, must live with.

Some consumers, not all.

I can easily tell you the 0-60 times for a number of vehicles - but horsepower? Fuggitaboutit. I just don't care. It's a squishy number.

 

[Andyw2100]

I think Tesla has been clear that the P85D L will not perform the same as a P90D L regardless. So even if the P90D L was improved to 10.9 second 1/4 mile today, that will not really tell you what to expect on the P85D L.

When Ludicrous was first announced the difference between a P90D with Ludicrous and an upgraded P85D with Ludicrous was supposed to be very small. I believe a number mentioned was a .1 second difference in the 0-60. I'm not suggesting anyone hold Tesla to that, because more recently Tesla has been much more conservative in their statements about what the upgraded P85D with Ludicrous would deliver. But there are some very knowledgeable people here--people like lola--who are hopeful that the original statements are closer to the truth, and the more recent ones statements are overly conservative, so that in that sense Tesla would, this time, under-promise and over-deliver.

So if the first upgraded P85Ds do only improve by .2 seconds, people won't know whether or not to keep hoping for more, or whether "that's it", since the P90Ds with Ludicrous should have an update coming (or Tesla missed a specification, and possibly they or Motortrend did something funky with the Motortrend car.)

The people who upgraded the P85Ds will have had the conservative specs met, so won't have anything to complain about. But I'm sure many of them, and many watching and waiting are hoping for the numbers originally announced back in July, which were "almost the same as the P90D with Ludicrous", or something along those lines.

Tesla should be saying something to current P90D Ludicrous owners already, since Tesla, at least for the moment, has missed a spec for them. What they would say, if they chose to say it, would have bearing on the P85D upgrades as well, one way or the other, though Tesla is not obligated to communicate anything more to this group than they already have.

 

[stopcrazypp]

Yep, this is exactly why the ECE R85 standard is so absurd. This standard does not benefit consumers at all.

stopcrazypp, you say that current standards for measuring engine/motor power all dictate that you take the engine/motor and attach accessories as appropriate. Whilst the gist is correct, the difference is that SAE actually requires you to attach the accessories that have an effect on engine performance, whereas ECE R85 discards a very crucial "accessory" — the battery — which is typically the limiting factor in an EV due to current technological constraints. And before you bring up your examples of manufacturers still using SAE gross hp today, I'd like to point out that, out of the thousands of car models on the market, only a couple of manufacturers and several non-mainstream models are still using SAE gross hp. I think this clearly shows that the majority of people expect to see SAE net hp these days.

Sure most automakers presumably use SAE net (I'm not certain though given automakers don't explicitly say so), but the fact there are automakers still using SAE gross and not making any note of it shows this is not necessarily something Tesla is liable for fundamentally. And even SAE net has plenty of holes for automakers to play games in getting the best numbers (as with the Camry).

Ultimately none of the standards I listed represents a number the consumer will ever see. The only number that the consumer can see is wheel horsepower, but no automaker advertises with that.

 

[jasonjax]

Congratulations?