MotorTrend Reviews the P85D--Quickest 4-Door Sedan Ever Tested

[Saghost]

That's (potentially) consistent with the idea that the front motor is geared longer than the rear motor. If so, even if the two motors are putting out the same overall total power as the single motor in the P+, the effective total gear ratio for that power would be taller, which would show benefits the faster you went.

The initial jump off the line might theoretically be worse in that scenario, except that we know that the P+ is heavily traction limited at low speeds. Giving away some theoretical low end pull for double the traction is a good trade.

Maybe. Using the chart I was given, here:

http://www.teslamotorsclub.com/attachment.php?attachmentid=47712&d=1398288415

It looks like the P85 is down to about 200 kW of output by 116 mph, meaning that a theoretical car that had enough motor headspace and suitable gearing to use the full battery output could possibly have 50% more power at that speed.

Without knowing more about how the chart was developed and what drives the car's limitations, I'm not sure how realistic that is for the D, but it's a big enough number that it could perhaps explain the observed performance, maybe.

A lighter ICE car is using 550 rated horsepower (~410 kW) to achieve slightly worse performance (but of course they can only hit the peak output momentarily here and there, and electrics are always faster for the same power rating due to the broader curves.)

(Either way, the data means that the car is showing substantially improved performance at high speeds, not merely 0-30, which is all I was trying to point out in the post above. )
Walter

 

[wallet.dat]

But in that case, why is the D so much faster above 60 mph?

But that's not what the data says. The D goes from 60-116 faster than the P goes 60-108, while being ~5% heavier.

Once you're at speed, weight becomes less of a factor than aero and overall motor power.

 

[JRod0802]

Maybe. Using the chart I was given, here:

http://www.teslamotorsclub.com/attachment.php?attachmentid=47712&d=1398288415

I'd love to see that same chart, but with the P85D on it also.

 

[WarpedOne]

As soon as I get the data, i'll update it. But not sooner

 

[Hans (Amsterdam)]

Motor Trend test data:

S85 60 - 110,9 mph in 8,2 sec
P85 60 - 112,5 mph in 8,4 sec
P85D 60 - 115,2 mph in 8,5 sec


source:
http://www.motortrend.com/oftheyear...rend_car_of_the_year_tesla_model_s/specs.html
http://www.motortrend.com/roadtests/alternative/1411_2015_tesla_model_s_p85d_first_test/

 

[Sad]

This seems to confirm that the P85D won't really have a dramatic increase in power above 60 mph... No miracle, the battery is the limiting factor. If confirmed, a bit sad that Tesla implied a 691 power figure, that all journalists put in their headlines, without clarifying matters shortly after.
That being said, looking forward to the P110D!!

 

[LetsGoFast]

Motor Trend test data:

S85 60 - 110,9 mph in 8,2 sec
P85 60 - 112,5 mph in 8,4 sec
P85D 60 - 115,2 mph in 8,5 sec


source:
http://www.motortrend.com/oftheyear...rend_car_of_the_year_tesla_model_s/specs.html
http://www.motortrend.com/roadtests/alternative/1411_2015_tesla_model_s_p85d_first_test/

Can you clarify your data for me? I get that the 110.9 112.5 and 115.2 are the trap speeds in the quarter-mile, but I don't find the 8.2, 8.4 and 8.5 second numbers in the reports. They aren't the quarter-mile times and I can't figure out what they are.

 

[ZsoZso]

Can you clarify your data for me? I get that the 110.9 112.5 and 115.2 are the trap speeds in the quarter-mile, but I don't find the 8.2, 8.4 and 8.5 second numbers in the reports. They aren't the quarter-mile times and I can't figure out what they are.

Simply math:
13.2 - 5.0 = 8.2
12.4 - 4.0 = 8.4
11.6 - 3.1 = 8.5
(QUARTER MILE time from the article MINUS 0-60 time from the article)

 

[Hans (Amsterdam)]

This seems to confirm that the P85D won't really have a dramatic increase in power above 60 mph... No miracle, the battery is the limiting factor. If confirmed, a bit sad that Tesla implied a 691 power figure, that all journalists put in their headlines, without clarifying matters shortly after.
That being said, looking forward to the P110D!!

I wouldn't worry too much about (lack of) speed of the P85D, especially when compared with a Nissan GT-R.

2009 Nissan GT-R with ( no ) launch control.
0-60 mph 3.2 sec (4.0 sec)
1/4 mile 11.6 sec (12.2 sec)

2015 Nissan GT-R Nismo with ( no ) launch control.
0-60 mph 2.9 sec (my guess 3.6 sec )
1/4 mile 11.1 sec (my guess 11.6 sec )

P85D no launch control
0-60 mph 3.1 sec
1/4 mile 11.6 sec

source:
2009 Nissan GTR - First Test - Motor Trend Page 2

So, Just How Slow is a Nissan GT R Without Launch Control Engaged?

http://wot.motortrend.com/1410_grea...ed_on_ignition.html?web=SIM:MT|Reviews:MT|WOT
Porsche 918 Proves 0-60 Times Are Total Bullshit

 

[Sad]

Actually, the P85D has an implicit launch control (or doesn't need one), due to the super-fast reacting traction control system and the fact that the engine has a flat torque curve at the beginning, i.e. no need to "rev" anything to be in the sweet-spot prior to launching.

 

[stevezzzz]

We've seen speculation that the front motor will likely be geared taller than the existing P85's rear motor. But what about gearing the P85D's rear motor? Any reason to think it's got a new gearbox, too?

 

[jerry33]

We've seen speculation that the front motor will likely be geared taller than the existing P85's rear motor. But what about gearing the P85D's rear motor? Any reason to think it's got a new gearbox, too?

No reason that I can think of. Both new would mean even longer delays in getting production up to speed.

 

[TEG]

I keep wondering how fast you could rev the rear motor past "redline" if the front motor was geared taller and was pulling at the top end.
If the rear motor doesn't have some kind of disengage clutch, then I would think you could start to have an issue with bearings and drag as you revved it really fast.
Perhaps the rear on the D is geared taller too, but the car can still accelerate faster due to both motors working together?
Doesn't the S85D have more range than the P85D? Maybe that is because both motors are geared tall on S85D, but P85D has to "overrev" the rear motor causing some efficiency loss, but allowing 'crazy' off the line acceleration?

I created a thread to ponder/discuss stuff like that here:
Dual drive techincal questions

 

[stevezzzz]

Thanks for the thread link, TEG. Good discussion over there.