New P90D does 1/4 mile in 10.8 and 0-60 in 2.8s. Question: Does P85D get any love?

[dennis]

I disagree. When an ICE manufacturer claims xxx hp, the expectation is that somewhere between the pistons and the wheels, at some RPM and speed, it can be measured to make xxx hp. Doesn't matter if half of the power is lost in the drivetrain, if it can be measured, you can claim it.

Similarly, the expectation was set that the P85D would make 691hp at some speed, somewhere between the battery and the tires. We now know that the maximum discharge rate at the battery is 100kw short of what would have been needed. A more apt ICE analogy is that while an engine is capable of xxx hp, it never makes more than 80% of xxx because the fuel line is too narrow to feed it the necessary gasoline.

Yeah, I get it, you are still hung up on the P85D not making 691 HP peak and putting some % of that to wheels. But you missed my point, which was that you can't just look at peak HP figures and expect to know how a car will perform across the acceleration spectrum. That's why measured performance like 0-60 and quarter mile times (and trap speeds) are much more indicative of how a car will perform than peak HP.

And to re-iterate: powertrain architecture has a much greater impact on performance than peak HP. For example, AWD cars accelerate more quickly to a point because of better traction, but may lose some of that advantage because of greater weight. Single gear EVs have high initial acceleration but eventually lose out to mechanical advantage. Turbo cars have greater output per displacement but may suffer in real world situations vs. normally aspirated ICE's because of turbo lag. Etc, etc.

 

[gordo]

Yeah, I get it, you are still hung up on the P85D not making 691 HP peak and putting some % of that to wheels. But you missed my point, which was that you can't just look at peak HP figures and expect to know how a car will perform across the acceleration spectrum. That's why measured performance like 0-60 and quarter mile times (and trap speeds) are much more indicative of how a car will perform than peak HP.

And to re-iterate: powertrain architecture has a much greater impact on performance than peak HP. For example, AWD cars accelerate more quickly to a point because of better traction, but may lose some of that advantage because of greater weight. Single gear EVs have high initial acceleration but eventually lose out to mechanical advantage. Turbo cars have greater output per displacement but may suffer in real world situations vs. normally aspirated ICE's because of turbo lag. Etc, etc.

I don't argue against any of these points. I simply argue that Tesla didn't provide the necessary information to make that determination at the October "D" event and instead allowed a 691hp figure to sit in its place, which, given a dearth of other performance details, put certain expectations around high speed acceleration. Was quarter mile time and trap speed presented in October?

 

[mkspeedr]

http://www.wired.com/2014/10/tesla-reveals-details-big-model-d-announcement/

0-60 in 3.2 I believe

 

[lolachampcar]

Apples and Oranges.....
If you do not know your fruit, it is prudent to go to school on it before you part with your hard earned cash. Lesson learned I guess.

 

[Andyw2100]

Apples and Oranges.....
If you do not know your fruit, it is prudent to go to school on it before you part with your hard earned cash. Lesson learned I guess.

I'm afraid the only lesson being learned by many is that we simply can't trust Tesla the way we thought we could.

 

[jcaspar]

I'm afraid the only lesson being learned by many is that we simply can't trust Tesla the way we thought we could.

Theres that drivetrain noise again....:smile:

 

[ecarfan]

New P90D does 1/4 mile in 10.8 and 0-60 in 2.8s. Question: Does P85D get any ...

I'm afraid the only lesson being learned by many is that we simply can't trust Tesla the way we thought we could.

The way you _assumed_ you could. And you assumed that a certain horsepower number would produce certain real world results, when of course the situation was never that simple, as has been explained in numerous posts in this thread.

 

[Andyw2100]

The way you _assumed_ you could.

I don't know what that means. What's the difference between THINKING we could trust Tesla and ASSUMING we could trust Tesla?

And you assumed that a certain horsepower number would produce certain real world results, when of course the situation was never that simple, as has been explained in numerous posts in this thread.

No. I BELIEVED Tesla when they said the car they were selling me would produce 691 HP. It's been shown that it produces no more than 530 HP. I, and many others, have a problem with that.

 

[lolachampcar]

My ICE said it produced 550 ft-lbs of torque and I measured it at 1800 rpm. They lied; it was nowhere near 550 ft-lbs.

Is MS capable of producing north of 650 hp with a battery that can only source (350V * 1300 amps or 455 KW / 750 HP/KW or 606 HP with perfect efficiency)? Absolutely not. Does the car perform? Absolutely yes. Does it perform at high speeds like an ICE. No and that is perfectly evident from a test drive. Apples and Oranges. You did not buy an ICE; you bought a BEV. If you are not capable of evaluating or understanding the difference then you should not be buying BEVs.

If you tell me something is green and I look at it and determine it is blue I can not, in good faith, come back to you after buying it and be mad because it is blue and not green.......

 

[Andyw2100]

If you tell me something is green and I look at it and determine it is blue I can not, in good faith, come back to you after buying it and be mad because it is blue and not green.......

Some of us did not possess the expertise to determine for ourselves that the color, to use your analogy, was not the color Tesla was telling us it was. Nor did we have any reason to believe they would be telling us it was any color other than what it really was.

Are you really making the argument that lay-people should have been able to figure out that the 691 HP claim was bogus? You clearly have a lot more expertise in this area than I do, so you may well have realized you would not be getting 691 HP. I, however, did not. I simply took Tesla at their word. I expected 691 HP to mean 691 HP and, back to your analogy for the color of the car to be green, since they told me the color was green.

 

[lolachampcar]

No, the argument I have heard over and over again is that MS does not perform like an Audi A7 (insert your preferred car here) above 60 mph (insert preferred speed here).

My point is the car does 0-60 in 3.2 seconds and the quarter in under 12 seconds. These numbers equate to a given amount of power for the weight of the car and this amount of power is consistent with the numbers Tesla is advertising.

I boil the complaints down to "MS does not do what an ICE does absolutely everywhere in the operating envelope with the same quoted HP numbers".

If you were Tesla, how would you try to transmit the performance of the car to world?

Do remember that I fundamentally agree that Tesla is pulling a fast one. Claiming a certain HP when the battery can not source that much instantaneous energy is NOT accurate. I just do not think it is a biggie. At the same time, I sympathize with Tesla's need to somehow transmit the capability of the car.

And in direct answer to your question, yes, if you are excitable about cars that have north of 600 hp then I expect you to know after a test drive that MS did not accelerate hard over 60 mph. Of course, what I do or do not expect is really not important in the overall scheme of life

 

[cynix]

New P90D does 1/4 mile in 10.8 and 0-60 in 2.8s. Question: Does P85D get any ...

if you are excitable about cars that have north of 600 hp then I expect you to know after a test drive that MS did not accelerate hard over 60 mph.

According to posts in this thread and elsewhere, the problem is that when people found this out during a test drive, they were told by Tesla staff that this is because the test drive vehicle is speed limited to 80 mph and power tapers off before reaching that limit. They were not told that this is simply the characteristic behaviour of the vehicle even if it wasn't speed-limited.

 

[tezzla]

Don't forget that we weren't allowed to test drive the car before December, most of us ordered in October. We had to go on (misplaced) faith.

 

[Andyw2100]

If you were Tesla, how would you try to transmit the performance of the car to world?

I'm not sure. As I said, I have no expertise in this area. What I --DO-- know is that I wouldn't provide inaccurate information.

Do remember that I fundamentally agree that Tesla is pulling a fast one. Claiming a certain HP when the battery can not source that much instantaneous energy is NOT accurate. I just do not think it is a biggie.

I agree that it wasn't --THAT big of a deal.

That being said, since they now, with the Ludicrous mode update, have the ability to get the car's HP closer to what they claimed it was before we purchased the cars, it seems to me that rather than selling that upgrade to us, Tesla should be providing it at no cost.

And in direct answer to your question, yes, if you are excitable about cars that have north of 600 hp then I expect you to know after a test drive that MS did not accelerate hard over 60 mph.

As an early adopter, I ordered my P85D without having been able to test drive one. (As a matter of fact, I ordered it without ever even having seen any Tesla of any kind in person.) None of the early adopters could have driven a P85D before ordering. Though I wouldn't have been able to identify the fact that the car didn't have the advertised HP, I expect, as you suggest, others would have. Had they posted about it here, I might have then learned about it, just as I learned about the issue now, after the fact--by reading about it.

 

[tezzla]

Just reading the last few threads, it sounds like Tesla could have said something like: Produces 691 HP*
*based on ICE performance standards



edit: no, I guess not. It is only 691* in the 0-60 spec.

 

[mkspeedr]

Like most people in this thread I am a car guy (and motorcycle guy). I have had this happen with Cobra Mustangs (under rated and required new exhaust) - Mazda RX8 that actually was bought back by Mazda because it didn't meet HP figures. Not to mention my Yamaha R6 that never hit the 17,000 rpm redline...


At least Tesla hit the 0-60 numbers. Hopefully Tesla learned a lesson and my P90D will be closer to the horsepower I want.

 

[sorka]

Just reading the last few threads, it sounds like Tesla could have said something like: Produces 691 HP*
*based on ICE performance standards



edit: no, I guess not. It is only 691* in the 0-60 spec.

Yea, that's the funniest part of argument that those who say you can't compare EV vs ICE hp ratings. Why is it funny? Because they're *exactly* right but in the wrong direction.

Any EV car making x amount of hp will kill any ICE car that makes the same x horsepower at one peak. EV performance curves are so much more favorable because they make pretty much peak hp at all RPMs, not just one. The amount of power it takes to accelerate from speed S0 to S1 is determined by how much power is applied under the curve. ICE engines have to use gears to stay as close as possible to their peak but they still put down lower power than their peak on either side of that peak as they accelerate through gears. Having to change gears takes even more time even with a DCT or equivalent.

The EV car doesn't have to make as much *peak * hp have the same acceleration performance as an ICE car because it's average hp applied under the acceleration curve is more for the same peak hp.

The problem here is the P85D makes so much less power than what is claimed that it's still not good enough to compete with ICE cars that have way less power once those ICE cars are already in their power band.

The P85D kills most cars from 0-60 but not because it comes close to making it's claimed 691 hp but because the power it does make it make *very* early.

You can't use a an ET calculator to calculate ET for an EV vehicle because those calculators assume typical power curves for ICE cars. There is no curve for EV cars. The curve is flat(mostly).

If you take the P85D off insane mode and leave it in sport, it will still make the same amount hp but it just does so later. Instead of hitting peak at 36 MPH, it hits peak at 60 MPH yet the ET is now 9 tenths of a second longer.

Watch all those drag race videos on youtube with P85Ds racing other cars that have worse power to weight ratios. The P85D always comes out swinging. Then after a few seconds, you almost always see the ICE starting to close the gap because it's accelerating faster than the P85D now. Sometimes the P85D still exits sooner but even in those cases, look at the slips posted at the end of each video. The ICE car with the way worse power to weight ratio always has a much higher speed. The P85D when it wins only wins because of the head start it got from 0-30 MPH which is usually considerable.

Just look at this acceleration chart over time between a P85D and a Hellcat.

The P85D weighs 10% more but the Hellcat's acceleration force is 50% to 60% more for most of this chart except the very beginning because we all know electric motors can produce all of their torque at 0 RPMs.

- - - Updated - - -

Like most people in this thread I am a car guy (and motorcycle guy). I have had this happen with Cobra Mustangs (under rated and required new exhaust) - Mazda RX8 that actually was bought back by Mazda because it didn't meet HP figures. Not to mention my Yamaha R6 that never hit the 17,000 rpm redline...


At least Tesla hit the 0-60 numbers. Hopefully Tesla learned a lesson and my P90D will be closer to the horsepower I want.

Mazda had a class action suite filed against them for overstating the hp on the RX8 by a *mere* 10hp. Most manufacturers understate their hp. Tesla did for the S85 and P85. The S85 is stated as 362 hp but an S85 at 90% dynos 375 rear wheel hp. The P85 was listed at 416 before before they revised it to 472. But since a P85 dynos at 430 to 436 at the wheels, it's still understated even now.

- - - Updated - - -

According to posts in this thread and elsewhere, the problem is that when people found this out during a test drive, they were told by Tesla staff that this is because the test drive vehicle is speed limited to 80 mph and power tapers off before reaching that limit. They were not told that this is simply the characteristic behaviour of the vehicle even if it wasn't speed-limited.

I was one of those that was told this on my test drive. It was limited to 80 MPH and I was told that because of this, power was tapered off long before this so that there wouldn't be a sudden decrease in acceleration. If anyone has ever hit the rev limiter in a fast car at speed, you know what I'm talking about

 

[tdelta1000]

I recently read that the P85D has a top see of 155MPH as does the 90. The P90 is a new machine all together.

 

[darthy001]

And in direct answer to your question, yes, if you are excitable about cars that have north of 600 hp then I expect you to know after a test drive that MS did not accelerate hard over 60 mph. Of course, what I do or do not expect is really not important in the overall scheme of life

As mentioned by others many had no way of getting a test ride... Test rides in Norway started the same week my car was delivered.. That was in february and I ordered 2hours after the design studio opened up in october

I dont really care that much about this, but I do feel tricked by Tesla. No doubt that the 691hp claim was a big selling point for many. For me the total package was the big deal and the performance just a fun addon....

Now I am more irritated that Tesla releases a new model before my car is even completely delivered, but that is anpther story

Still considering the upgrade, and will be eagerly awaiting your rwporting on that!

 

[stilgar]

If you were Tesla, how would you try to transmit the performance of the car to world?

They have changed the way they present the car’s power twice since I bought it, and the way they’re doing it now is much better than it was originally. To me, this is a strong indication they noticed they’re making people angry. Sadly, that is little consolation for me.

I’ll be waiting to test-drive a P90D, see if it performs better in speed ranges that I care about, then decide what to do next.