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There's A New Sheriff In Town And Auto Experts Know It

There's A New Sheriff In Town And Auto Experts Know It

"In the options selection, you'll be able to choose [between] three settings: Normal. Sport. And Insane." Elon Musk glanced around and grinned.

"Yeah, it will actually say 'In-sane.'"(Musk again)

"Our goal was to match one of the fastest cars ever made: the McLaren F1." Somewhere in England, Gordon Murray's porcupine eyebrows have just elevated three inches. Can the F1 designer's fabled carbon-fiber, 627-hp, Ferrari-humbling masterpiece actually be paced to 60 mph by a five-seat sedan with a trunk sized for a Home Depot haul?

Twenty-two years ago, the McLaren F1's time of 3.2 seconds to 60 mph was the technological redline of what a mad genius Grand Prix designer could conjure from a road car. I tested one back in the day, and although it was at a closed airstrip encircled by acres of table-flat run-off room, it was among the most shattering few seconds of my life. One moment everything was still; the next, the cabin had exploded in a maniacal machine racket. The tach needle swept clockwise, the clutch pedal fought my left foot's stabs, the shifter pinballed through its detents, the V-12 engine charged through its revs again, my right foot feared staying planted but did anyway, everything shook, and I just hung the hell on as the world melted into a smear. Exhale. Launch one of Musk's Falcon 9 rockets horizontally, and you'll get the idea.

But scrambling to the same 60 mph time in the P85D bears no resemblance to that at all. With one transmission gear and no head-bobbing shifts, it's instead a rail-gun rush down a quarter-mile of asphalt bowling lane. Nothing in the drivetrain reciprocates; every part spins. There's no exhaust smell; the fuel is invisible. The torque impacts your body with the violence of facing the wrong way on the train tracks when the whistle blows. Within the first degree of its first revolution, 100 percent of the motors' combined 687 lb-ft slams the sense out of you. A rising-pitch ghost siren augers into your ears as you're not so much accelerating as pneumatically suctioned into the future. You were there. Now you're here.

The wormhole between the two is courtesy of a second motor on the front axle. At 221 hp, it's smaller than the P85+'s existing 470-hp rear machine (total: 691), and for the non-Performance 60- and 85-kW-hr Dual Motor Model S, it'll be the rear motor, too. Lift the front trunk's lid (the frunk, they call it), and you're struck by how much all of this was anticipated back when the Model S was penned. What was a recessed cavity near the firewall becomes the new forward engine room with enough left to swallow a duffle bag and retain its terrific 5-star frontal crash performance. Equal-length front halfshafts thread through new branched chassis rails and hub uprights—and that's about it.

Replacing the now-discontinued P85+ as the apex Model S, the P85 Dual Motor gains 197 pounds, tipping the car's weight distribution from 47/53 (f/r) to 51/49. Anti-roll bars and shock valving are suitably thicker and firmer, but the Michelin Pilot Sport PS2 tires are the same, as is the car's 0.91 g of lateral grip. However, around our quirk-exposing figure-eight course, the D's handling wasn't Novocained by the added nose heft (as you'd expect), nor was its steering garbled by torque-steer cross-talk (as you'd expect); instead, all four tires now want to be in on the traction action. Feathering the accelerator (or rather, the accelerator pedal's potentiometer) now rotates—and also bends—the car's trajectory via regen brake drag that instantly reallocates between both axles (no longer limited to the rear). Essentially, the two motors' email-instant reflexes mean the stability control system is the drivetrain itself—and vice versa—not a Band-Aided layer of throttle- and brake-mitigating technologies overlaid on a big-inertia crankshaft and flailing pistons accustomed to Pony Express reaction times.

Consequently, the easiest way to flatten your retinas at a dragstrip isn't by just stomping on the right pedal. Instead, you draw your foot back and kick the living hell out of it. (I'm serious.) Your foot's flying start at the pedal means the potentiometer opens the battery's electron floodgate that much sooner, and without the teeniest tire chirp, the P85D accelerates at the highest rate the road's mu (its coefficient of friction) allows. It's surreally efficient. And it's so fast off the line that the slower-sampling rate of our two high-frequency GPS data loggers was actually missing some of the action; within the first 1/20th of a sec (not even the "O" in "One Mississippi") the car was already going 0.7 mph. To 30 mph the P85D would be four feet ahead of the fastest-accelerating sedan we've tested, the Audi RS 7, a gap that holds to 60 when the Tesla punches the clock at 3.1 seconds, a tenth quicker than the Audi (as well as the McLaren F1's accepted time -- all of these after subtracting the customary 1-foot rollout). Both cars arrive at the quarter in 11.6 seconds, with the Audi starting to show its higher-speed chops. (The P85D tops out at 155, the RS 7, 174 mph.) Great for the Autobahn, irrelevant in America.

When you're not doing a hole-shot, the dual motor setup can offer slightly better overall range (about 4 percent better for non-Performance versions, 3.5 percent less for the P85D) by mixing and matching the twin motors' slightly different power curves. It also might better distribute the tire wear, as its regen is now biased toward the front instead of the aft rubber, which worked overtime in the rear-drive cars.

Meanwhile, the Model S has undergone a quiet mid-cycle refreshing with better standard seats, terrific-looking and highly bolstered front and rear performance seats in the P85D (even in the back!), better whiplash protection, revised (and more conventional) steering column stalks, wider-opening rear doors, a self-closing charge port door, and bigger sunvisors. Everything's better. During a chat with Musk at the P85D's introduction, he mentioned that on average, Tesla implements about 20 modifications to the car per week. Not software, mind you, but actual hard parts. Per week. Adding the Dual Motor to either the 60- or 85-kW-hr cars tabulates to $4,000; it's $11,100 in frosting to a P85 (including the high-power rear motor).

From a quarterly report standpoint, the across-the-range availability of an all-wheel-drive option will assuredly boost Model S' Slippery State sales, and—duh—it was going to be central to the upcoming Model X anyway. But the world's preeminent automotive showman also knows there's no better way to stir imaginations among Tesla fence-sitters—and churn up heartburn in Bavarians—than by conjuring a hulking, pacing alpha male version of the Model S like this. How will the psychological landscape among the One Percenter Mercedes-Benz AMG, Audi RS, and BMW M crowd be recast if, when a Tesla Model S P85D rolls up at a light, it's game over, guys? Brace yourself, Teutonic Status Quo, because the quickest-accelerating sedan in the world isn't German anymore. It's from California. As they say in Palo Alto: Auf Wiedersehen!

According to Kim Richards at Motor Trend, other drivers should get use to this view of the Model S P85D!
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Details:

BASE PRICE ~ $105,670
PRICE AS TESTED ~ $120,170
VEHICLE LAYOUT ~ Front & rear motor, AWD, 5-pass, sedan
MOTORS ~ AC induction, 221-hp/244 lb-ft front; 470-hp/443-ft-lb rear, (691-hp/687-lb-ft comb)
TRANSMISSION ~ 1-speed automatic
CURB WEIGHT (F/R DIST) ~ 4830 lb (51/49%)
WHEELBASE ~ 116.5 in
LENGTH x WIDTH x HEIGHT ~ 196.0 x 77.3 x 56.5 in
0-60 MPH ~ 3.1 sec
QUARTER MILE ~ 11.6 sec @ 115.2 mph
BRAKING, 60-0 MPH ~ 113 ft
LATERAL ACCELERATION ~ 0.91 g (avg)
MT FIGURE EIGHT ~ 25.0 sec @ 0.77 g (avg)
EPA CITY/HWY/COMB FUEL ECON ~ MT est 85/87/86 mpg
ENERGY CONS., CITY/HWY MT ~ est 40/39 kW-hrs/100 miles
CO2 EMISSIONS, COMB ~ 0.00 lb/mile

http://www.motortrend.com/roadtests/alternative/1411_2015_tesla_model_s_...
http://www.gq-magazine.co.uk/entertainment/articles/2014-11/17/tesla-p85...

David N | 21 November, 2014

great post.

Brian H | 21 November, 2014

Had missed the 1-foot rollout note for the 3.1 time before.

"get used to"

Juggernaut | 21 November, 2014

Mighty fine writing. I suppose I should believe it because it sounds like it's reported from experience; Meanwhile, having yet to see a Tesla in person must consider this a fancy illusion or something Californians do that this Alabaman has yet to fathom even in imagination. Even if that's the case it's good writing and the pictures made it even easier to read.. Thanks for sharing...

Scott Flowers

Mike83 | 22 November, 2014

Very exciting. It is a bargain price and no gas, oil, radiator fluid, catalytic converter or tune ups required. And it appears any driver who is fairly decent can have the same performance every time they drive without having clutch or engine issues.

blue adept | 24 November, 2014

@Brian H

My intention was to lend the term a present-tense context (as in something that one needed to do) instead of a past-tense context (as in something one was accustomed to doing).

Satisfied now, Grammar Troll?

blue adept | 24 November, 2014

@David N & flash2911

Thanks guys!

I felt that the POV was worth the effort to mashed it up from two(2) different articles scattered across three(3) different sites to post here for the benefit/pleasure of all.

blue adept | 24 November, 2014

@Mike83

I think that that's one of the underlying ideologies behind Tesla Motors...

Providing the World with a relatively trouble-free, eternally free form of clean, conflict-free, environmentally and Human friendly transportation without any compromises.

Brian H | 25 November, 2014

allusion;
Nope. There is no present tense version of that expression. Incoherent. Means adjusted or habituated to, in the habit.

blue adept | 25 November, 2014

@Brian H

If you came here to teach people English or Grammar, or even grammatical syntax, then you came to the WRONG place!

Why not try commenting on the actual subject of the thread, you know, like an intelligent, mature, educated adult would instead of behaving like some juvenile, antagonistic, troll?

I ask because it is apparent, judging by your overly minimalistic commentary that, if you could manage to do any better you would have long before now.

Haters gonna hate I guess:

http://www.youtube.com/watch?v=nfWlot6h_JM

Grinnin'.VA | 25 November, 2014

@ just an allusion | November 24, 2014

Providing the World with a relatively trouble-free, eternally free form of clean, conflict-free, environmentally and Human friendly transportation without any compromises.

Have you heard of that magic bridge in Brooklyn that's for sale?
For a very good price! Would you believe,"FREE"?

BTW, many real people would like to buy a $100k MS with a range of 500 miles. Somehow, Tesla didn't quite deliver that. But, you insist, the MS doesn't involve "any compromises". Amazing!

Go Tesla!

Brian H | 25 November, 2014

allusion;
reduced to the specially low-Q haters insult loved by the low-Q progressives? My sympathies.

blue adept | 25 November, 2014

@Grinnin' @us.VA

Tesla Motors never claimed a '500 mile range' capable Model S, but this is a technological application that is still very much in its infancy so there's really no telling at this point what the future will hold, though it's looking very promising, afterall, Tesla Motors has only been around since '03 and they've already achieved a BEV capable of a 300 mile maximum range (the Model S)!

Just saying.

blue adept | 25 November, 2014

@Brian H

I ain't sweating it.

Red Sage ca us | 25 November, 2014

Nothing wrong with expanding upon the means by which we expound while attempting to communicate using keyboards on the internet.

Grinnin'.VA | 26 November, 2014

@ just an allusion | November 25, 2014

Tesla Motors never claimed a '500 mile range' capable Model S, ...

Of course not. I didn't suggest that they made such a claim. My 'claim' is that there are many potential Tesla owners who want a BEV with a '500 mile range'. My observations are:

1. Tesla is quite aware of the fact that many of their potential customers want more range than the MS delivers.
2. Tesla has delivered the MS with its current limited range only because they haven't yet figured out how to deliver more range while meeting other goals. Specifically, Tesla places a large emphasis on low 0-60 times.

IMO, the idea that Tesla's engineering doesn't involve 'compromises' it ludicrous. Virtually all product engineering requires at least a few tradeoffs and 'compromises'.

Whenever I read the words 'no compromises' in marketing (TV ads, promo interviews, etc.) I automatically recognize that as marketing hype, not reality.

Go Tesla!

but this is a technological application that is still very much in its infancy so there's really no telling at this point what the future will hold, though it's looking very promising, afterall, Tesla Motors has only been around since '03 and they've already achieved a BEV capable of a 300 mile maximum range (the Model S)!

Model ☰ | 26 November, 2014

@Grinnin'
Virtually all product engineering requires at least a few tradeoffs and 'compromises'.

You're absolutely right about that. But it's not what is meant when they say that "Model S" is "without compromise". It has not done any of the "normal" compromises that EV's supposed to do.

It isn't slower then "a normal car", not less powerful, less beautiful, less roomy, etc. It even has a great range, and a fast and wide charging network, and can with ease go on a long trip.

So, compared to a "normal" EV, it has no compromises - it's just a normal car that happens to have an electric drive-train.

Grinnin'.VA | 26 November, 2014

@ Model ☰ | November 26, 2014

... But it's not what is meant when they say that "Model S" is "without compromise". It has not done any of the "normal" compromises that EV's supposed to do.

I don't know what you mean by 'the "normal" compromises that EV's supposed to do'.

I interpret your comments to mean that you like the engineering tradeoff compromises made by the MS development team. Right?

When I read "without compromise", I think the writer is asserting that there is no 'compromise' tradeoff involved - that the writer means what she/he writes. Rather silly of me, isn't it?

Go Tesla!

blue adept | 26 November, 2014

@Grinnin' @us.VA

Well, you did say:

BTW, many real people would like to buy a $100k MS with a range of 500 miles. Somehow, Tesla didn't quite deliver that.

Which, IMHO, implies that such was expected from Tesla Motors, wouldn't you have to agree?

Be that as it may, your heart seems to be in the right place, just allow me to encourage you to be more careful with your wording in future communications to discourage any potential for generating misunderstanding or confusion.

Oh, for want of what the future holds!

blue adept | 26 November, 2014

@Model ☰

+1

Proper contextual application is necessary to insure against misunderstood syntactical expression.

blue adept | 26 November, 2014

@Grinnin' @us.VA

Wait for it....

vgarbutt | 26 November, 2014

Well, EM did say they could have a 500 mile range ev but it would be too expensive.

Model ☰ | 27 November, 2014

@Grinnin'
When I read "without compromise", I think the writer is asserting that there is no 'compromise' tradeoff involved - that the writer means what she/he writes. Rather silly of me, isn't it?

But as you stated above - there is no thing like "no compromises" in engineering. Engineering is - in this context - about making the right, and fewest possible, compromises. There is always the compromise between easy to park (in cityes) vs. storage- and living-room in the car. Between safety vs. range/consumption vs price etc.

Therefore a plea of "no compromise" have to be inserted in their proper context in order to give some meaning. As I did in the above post.

I interpret your comments to mean that you like the engineering tradeoff compromises made by the MS development team. Right?

Not necessarily, but to a large extent as they seem reasonable to me, not that one can not debating or criticize individual choices. Eg. you mention longer range. Sure, could well see for me a Tesla with an even longer range, but it must necessarily be one compromise between range and cost. And there we are back at this where is always has to be a compromise ;)

Brian H | 27 November, 2014

Perfection on first attempt without compromises is pixie dust stuff. Demanding it is stuff of a much browner, moister, and heaver sort.

Red Sage ca us | 27 November, 2014

Grinnin' Ron wrote, "Tesla has delivered the MS with its current limited range only because they haven't yet figured out how to deliver more range while meeting other goals. Specifically, Tesla places a large emphasis on low 0-60 times."

The limitation on range comes down to battery capacity and consumption rate. The 3-12 seconds it takes to get to 60 MPH is of no consequence over the full range of a vehicle... Unless someone decides to do maximum acceleration to 60, followed by coming to a complete stop without regeneration, then do it again, over, and over, and over again, for the whole day. It is highly unlikely that people will do

If you limit top speed, you can get greater range, from a smaller capacity.

I think the best range rating that the EPA currently gives is something like 270 Wh per mile. Their formula assumes an 85% loss 'from the wall' to the car. So that means the actual driving usage would be 230 Wh per mile. Thus, an 85 kWh battery pack, expended at 230 Wh per mile, would allow a range of 370 miles.

But wait... Someone has already managed around 420 miles of range with the Model S! They did it by driving very, very slowly, hypermiling, coasting, maximizing regeneration. That is the only way to do it with only 85 kWh of stored energy on tap.

It is not currently possible to operate a highway capable electric vehicle at 'typical highway speeds' to get a 500 mile range without making serious concessions in design.

To put it another way... If you operate an electric vehicle at 450 Wh per mile over the course of 500 miles... You will have expended 225 kWh of energy.

Does Tesla Motors offer a version of the Model S with a 225 kWh battery pack? No. They don't.

To put it another way... Say you have a gasoline car with a 20 gallon fuel tank. The stored energy potential is something like 672 kWh. If the vehicle gets 25 miles per gallon, that is 500 miles range.

Hey look, that's equivalent to 1,344 Wh per mile. Basically three times the energy expenditure rate of a hard driven Tesla Model S.

Most people who own a Tesla Model S report their average usage works out to between 280 Wh and 320 Wh per mile. Let's split the difference and use 300 Wh per mile as a benchmark. So over 500 miles they would expend a total of 150 kWh of energy.

Thus, if a version of the Tesla Model S existed that had 170 kWh of capacity, twice that of the Model S 85, then you could typically achieve a range of 500 miles without issue. 170 kWh is roughly the equivalent of 5 gallons of gasoline energy. So in the earlier example, that required 20 gallons at 25 MPG, you can cover the same distance much more efficiently using an electric vehicle.

Even if it can do 0-60 in 3.2 seconds.

Grinnin'.VA | 27 November, 2014

@ just an allusion | November 26, 2014

Well, you did say:

BTW, many real people would like to buy a $100k MS with a range of 500 miles. Somehow, Tesla didn't quite deliver that.

Which, IMHO, implies that such was expected from Tesla Motors, wouldn't you have to agree?

NO.
Tesla and its customers have many goals.
In designing and engineering the MS, Tesla made lots of choices about the tradeoffs involved. Higher ranges was a very common goal, both for Tesla's management and many of its customers.

Nothing I've written implies that I or anyone else expected the MS to achieve a range of 500 miles. My point is that many prospective MS buyers would like an MS with a 500-mile range.

Elon's comment about Tesla's ability to achieve a 500-mile range at much greater cost clearly indicates that he is aware of a broadly shared desire for higher ranges. Given Tesla's other goals, I agree with their decision to engineer the MS to cost about $100k with under 300-mile range instead of a $500k car with a higher range.

However, cost vs. range isn't the only 'range tradeoff' involved. Tesla could have designed the MS as a lighter, smaller, sleeker car with the same drive train that it has. That would have increased its range. Tesla decided to build a 5-passenger sedan with its current range instead. I agree with that decision as well.

IMO, Tesla could have built a car with less impressive acceleration and greater range. They chose to go with more acceleration and less range. Tesla and most Tesla owners seem to like that decision. I'm not confident of the wisdom of that.

I'm not even confident that Tesla ever seriously considered building a car with greater range and less acceleration. I have asked Tesla management to consider building such a car in the future. When I have suggested this on these forums, I was belittled and insulted by 'performance car' enthusiasts. No one, however, has presented a rational reason why it wouldn't be a good thing for Tesla to do.

Go Tesla!

Tiebreaker | 27 November, 2014

Some people are anal. But then some people are anal.

Brian H | 27 November, 2014

Tesla had to establish a 'rep' to get the attention it has.

Red Sage ca us | 27 November, 2014

Grinnin' Ron wrote, "IMO, Tesla could have built a car with less impressive acceleration and greater range. They chose to go with more acceleration and less range. Tesla and most Tesla owners seem to like that decision. I'm not confident of the wisdom of that."

You have stated this... opinion... several times. I truly do not understand why you insist that the possibility of quicker acceleration eliminates the availability of greater range. As I stated above, the math and real world examples do not support that conclusion.

Tesla Motors could have limited acceleration and left the 130 MPH top speed in place. Tested by the EPA on a five cycle test, the range would have been the same.

Tesla Motors could have both limited acceleration and set the top speed to 85 MPH or less. That could have been done by a combination of less aggressive gear ratio as well as software limitation. That might have increased range, but it is more likely it would simply force the car to never go below a certain minimum range, rather than increasing the maximum range.

Tesla Motors chose the appropriate balance of resources they had on hand... Not as a tradeoff, but as a conscious decision, and a planned goal... in my opinion.

Grinnin'.VA | 28 November, 2014

@ Red Sage ca us | November 27, 2014

You have stated this... opinion... several times.

Yes. And as I recall you've done the same. So what?
My guess: You don't like my opinion. So you subtly suggest that it's illegitimate for me to express my opinions in a series of posts. If that's your position, why is it OK for you to do the same thing?

I truly do not understand why you insist that the possibility of quicker acceleration eliminates the availability of greater range.

I don't think this paraphrases my opinion accurately. I believe that there is an engineering tradeoff between quick acceleration and range. That is, if Tesla tried to design a drive train to increase the range while increasing the 0-60 times, they could do so.

I believe you are one of the 'performance car' enthusiasts who has said that you don't want Tesla to do such a thing even if they could. I do NOT challenge your right to hold such a preference. I merely insist on my right to disagree with you.

Tesla Motors chose the appropriate balance of resources they had on hand... Not as a tradeoff, but as a conscious decision, and a planned goal... in my opinion.

I disagree. The technology involved either does or does not offer tradeoff options. That doesn't depend on your opinion or mine. I'd like to hear from JBS on that. AFAIK, he hasn't addressed this topic in public. (I have conveyed my opinion to him directly by email.)

BTW, I have one request for you: When you include quotes from my posts in your posts, please do not alter my words in any way.

Go Tesla!

Model ☰ | 28 November, 2014

@Grinnin'
That is, if Tesla tried to design a drive train to increase the range while increasing the 0-60 times, they could do so.

Here I disagree with you. I think, in opposite to combustion engines, that there is no such "trade off" in an electric motor.

I believe you are one of the 'performance car' enthusiasts who has said that you don't want Tesla to do such a thing even if they could.

Here I do agree with you - IF it was possible to do it, I would very much prefer longer range over high performance. But I don't think it's possible. 

The one thing they could change is the transmission. But unless they make it so that the motor is running at it's most effective at the speed your driving, it wont help. To make that, they need to do the same trick that fossil engines do: have a full gearbox, with the extra weight and complexity and effective loss that this brings.

Earl and Nagin ... | 28 November, 2014

@Grinnin,
While many of us appreciate your desire for more range, you still clearly don't understand EV range and acceleration.
The simplest way to think about EVs is that, given a particular weight, battery size, and air drag (essentially vehicle size):
The way to get more range is to design for less electrical resistance. Essentially, you need to put more copper wiring between the battery and the driveshaft. You also want to make the car as light as possible.
The way to get more acceleration is to design for less electrical resistance. Essentially, you need to put more copper wiring between the battery and the driveshaft. You also want to make the car as light as possible.
Do you notice the similarity between the preceding paragraphs? The only different word is range -vs- acceleration
Sure, you might be able to save 10 or 15 lbs in your driveshaft and motor mounts and handle less acceleration but those 10 or 15 lbs won't make a noticeable difference in the range (maybe a few 100s of more feet of range per charge)
The only real compromise that I see between range and acceleration that Tesla has made is to use 'sticky' tires to get more grip. Less sticky or grippy tires would cause less wheel drag and increase range at the expense off acceleration. They would also have reduced stopping distance making the car less safe. This means that Tesla can rationalize the sticky tires as increasing safety or increasing acceleration at the expense of range. One also can choose the Performance package and larger tires or the regular package to get even stickier tires to further shift the priority towards acceleration instead of range.

Grinnin'.VA | 28 November, 2014

@ Earl and Nagin ... | November 28, 2014

The simplest way to think about EVs is that, given a particular weight, battery size, and air drag ...: The way to get more range is to design for less electrical resistance. ... The way to get more acceleration is [... the same].

That's your understanding/opinion. I suspect that it's oversimplified. I can't prove I'm correct. Tesla could clarify this by releasing more technical information. Do you have a reference or link to information supporting your understanding?

Hopefully, Tesla will release more technical information about the AWD drive trains -- "soon".

Go Tesla!

Earl and Nagin ... | 28 November, 2014

@Grinnin,
I'm not quoting Tesla. This is basic EE. It isn't really Tesla's (or my) job to teach that just to keep the uninformed from complaining. I think that the fact that the AWD drivetrain increases torque and range should be a good real-world indication that both range and acceleration increase with more copper (two motors).
I'll caveat my comment that if you actually use the extra torque that more copper can provide you, you won't get more range. If you only 'ask' for normal torque, you'll get more range from a larger motor.
(using the following conventions:
I = current (amps)
V = Voltage (volts)
R = Resistance (ohms)
P = Power (watts)
)
The simple explanation is that torque is proportional to current (P~I). Wire loss Power (affects range) is also proportional to current (P=IV)
A battery provides a fairly fixed voltage V. Ohm's law tells us that current and voltage are related by V=IR. If you want to increase I for more torque from the battery, you reduce R (more copper). If you want to reduce the amount of Wire loss Power to increase range, you also want to reduce R (from P=IV and V=IR, we can see that Pwire=Isquared Rwire. note that I is dominated by the effective resistance from the motor).
If you want to reduce electrical losses, reduce Resistance.
If you want to increase torque, reduce Resistance.
Aren't electric motors great? That's what much of the 'no compromises' that many of us speak of is all about.

Brian H | 28 November, 2014

Seems in effect the trade-off choice has moved from the mfr's hands to the driver's. So Grinnin' doesn't want the driver to have that choice? An authoritarian tendency?

Earl and Nagin ... | 28 November, 2014

@BrianH,
Let's go a little easy on Grinnin' There's nothing wrong with trying to point out that some of Tesla's features may not be as important to some as they are to others, especially if there's an incorrect assumption that the desired traits come at the expense of the undesired ones. The only problem is that when one tries to apply assumptions for one paradigm to another one misses key benefits.
I could have just let Grinnin' complain but I figure I might be able to save him some effort and help him get over the un-warranted guilt and embrace the fun side of a lot of torque.

Grinnin'.VA | 28 November, 2014

@ Earl and Nagin ... | November 28, 2014

This is basic EE. ...

I believe the S85D has more range than the P85D. (I know that the difference is minor.) Let's assume that the AWDs represent Tesla's latest technical state-of-the-art. What causes the S85D to drive farther at 65 mph than the P85D? Note that both the front motor and the rear motor of the "P" are more powerful than the motors in the "S". If more current delivers both the lowest 0-60 times and the highest ranges, how can this be?

BTW, I haven't seen any evidence that either of the AWDs was engineered to maximize its range while achieving some level of 'performance'. At the AWD introduction event Elon proudly announced that the P85D was engineered for a 0-60 time of 3.2 seconds. He said that that was the goal for the P85D. AFAIK, Tesla executives have never publicly addressed the question of whether they could make a car with slightly more range and slightly higher 0-60 times.

Can someone, anyone please provide a reference or link to a qualified expert showing that there is no tradeoff between range and acceleration for BEV technology? [If you can't, I think you should admit that.]

Wire loss Power (affects range) is also proportional to current (P=IV)
... we can see that Pwire=Isquared Rwire. note that I is dominated by the effective resistance from the motor).

Can you elaborate on "I is dominated by the effective resistance from the motor"? To me your formula says that increasing I (using more torque) increases Pwire more than decreasing Rwire does.

As a general proposition, it seems to me that the way to increase range is to minimize the current required to achieve acceptable performance (speed & acceleration). If I'm incorrect, I would sure love to know what error I've made. Please enlighten me.

Go Tesla!

carlk | 28 November, 2014

@Grinnin'

Can we put this to rest now? Unlike ICE there is little or no range penalty for high power output capability in a EV in the first order. It's just simple physics.

Thank you.

Grinnin'.VA | 28 November, 2014

@ carlk | November 28, 2014

Can we put this to rest now?

NO!
No one has provided a reference or link to a technical expert backing up your claim. And now you think I should just forget about it! Amazing gall. If you can't provide the reference or link, you should admit that instead of trying to silence me.

I refuse to be intimidated or bullied into silence.
There is no law of physics that requires you to read my posts.

Go Tesla!

Earl and Nagin ... | 28 November, 2014

@Grinnin',

Don't worry, I'm not giving up on you, nor do I intend on bullying you. I know you are sincere and want to share the technology with you. Unfortunately, I was made aware of these relationships from working alongside experts, not from books or other documents that I could easily point you towards.
I strongly suspect that the P85D gets worse mileage than the S85D because of the tire compromise I mentioned. Stickier/grippier tires of the "P" will cause a lot more drag. In otherwords, the "P" is optimized for performance (no secret) while the regular isn't. I haven't gleaned this directly from Tesla folks who have done the real numerical analysis. I can only look from the outside and formulate reasons to explain what I can see.
You're also correct that the I dominates the Pwire more than the R. That is why I pointed out that "if you actually use the extra torque that more copper can provide you, you won't get more range. If you only 'ask' for normal torque, you'll get more range from a larger motor." Consistent with your and my mutual understanding, I suspect that a "P" with a floored accelerator will draw slightly less current than a regular model also floored but its probably so close it would be hard to measure if anyone who floors it really is caring at the time.
The point is that I suspect if you take a P85D, an S85D, and an S85, put the same wheels on all 3, and lock their cruise controls at 65 mph; the P85D will go farthest, followed by the S85D, then the
s85. This is because of the amount of copper between the battery and the driveshaft. With its stock performance tires, it is hard to tell how the P85D would stack up without knowing the numbers.

ps. We've been grinnin' for over 6 years as of last week!

Go Tesla!

Grinnin'.VA | 28 November, 2014

@ Earl and Nagin ... | November 28, 2014

I strongly suspect that the P85D gets worse mileage than the S85D because of the tire compromise I mentioned.

You may be right. Since the P85D has optional 19" wheels, we should find out. Hopefully Tesla will tell us.

The point is that I suspect if you take a P85D, an S85D, and an S85, put the same wheels on all 3, and lock their cruise controls at 65 mph; the P85D will go farthest, followed by the S85D, then the
s85.

Maybe. But AFAIK we don't know enough. We don't know the gear ratios for the AWDs. We don't know the split of current between the front and rear motors. All of these cars share the same body; they differ in weight. And more weight does increase the 'rolling resistance' of the tires. IMO this question is beyond our ability to determine at this point.

ps. We've been grinnin' for over 6 years as of last week!

Congrats. And thanks for being there as early adopters who helped Tesla when it needed help most.

Go Tesla!

Model ☰ | 28 November, 2014

@Earl and Nagin ...
I strongly suspect that the P85D gets worse mileage than the S85D because of the tire compromise I mentioned.

The new motors are supposed to be more energy effective then the old type, and while the S-D model has two new motors - one front and one rear, the P-D model has a new motor in the front and one "old" (less effective?) in the rear. It may be a part of the reason for the difference.

... and remember that this new range is specified at 65 mph, and this is probably the most effective speed with this new dual-drive system. Not sure you get any more range in let's say 50 mph then earlier.

Grinnin'.VA | 29 November, 2014

@ Model ☰ | November 28, 2014

... and remember that this new range is specified at 65 mph, and this is probably the most effective speed with this new dual-drive system.

Keep in mind that the S85D uses two motors that are different from the front motors of the P85D. I'm not at all sure that the 'most effective speed' of these two different drive trains is the same. I suspect that it would be wise if Tesla designed them to operate most efficiently at about 65. I just don't know enough about the designs.

Go Tesla!

Model ☰ | 29 November, 2014

@Grinnin'
Keep in mind that the S85D uses two motors that are different from the front motors of the P85D.

True - I guess... I know this motors has a different stated performance, just like it was for the motors of S85 and P85(+) earlier. Most of this differences I suspect was - and still is - in the inverter. So not much differences - if any at all - between the motors.

Which speed that gives the best performance is determined to a large extent by the difference in the transmissions/differentials. And I guess this is the same in the S-D and P-D. But just a guess...

tinsoc.us | 29 November, 2014

great post.

Grinnin'.VA | 29 November, 2014

@ Model ☰ | November 29, 2014

Keep in mind that the S85D uses two motors that are different from the front motors of the P85D.

Which speed that gives the best performance is determined to a large extent by the difference in the transmissions/differentials. And I guess this is the same in the S-D and P-D. But just a guess...

That's a reasonable guess. But only a guess.

Tesla HQ has explained the delayed availability of the S85D compared to the P85D as due to a need to complete testing of the S85D motor. Either they are blowing smoke, or it's a different motor than the front motor of the P85D.

Go Tesla!

Bikezion | 29 November, 2014

Grinnin;
Take a small block of wood, put it under the accelerator pedal of your model S. There. You just ruined-no-optimized the acceleration of your model S and maximized the range! Problem solved. You gained about 12 feet! Congrats. ;)
Go (slowly) Tesla!

Red Sage ca us | 29 November, 2014

Grinnin' Ron: I don't believe I made any alterations to your words when quoting them. Above, I quoted you in full, and added emphasis to denote the portions of the quote I was concerned with in the reply. I do not mean any harm, disrespect, or insult to you in any way. I'm just trying my absolute best to make sure that our discussions are as complete as possible, to ensure our communication in this medium is as thoroughly comprehensive as we can manage.

Perhaps you have changed your opinion at some point. When I summarize, or paraphrase, what you have said, it is mostly to illustrate what I believe you were attempting to communicate. If that is inaccurate, just say so, and restate, reiterate, or rephrase your position as you see fit. I have no problem with that. After all, that is what I am doing.

For instance, I noted in a reply here that you may not quite understand my position. You wrote, "I believe that there is an engineering tradeoff between quick acceleration and range. That is, if Tesla tried to design a drive train to increase the range while increasing the 0-60 times, they could do so." You followed that with, "I believe you are one of the 'performance car' enthusiasts who has said that you don't want Tesla to do such a thing even if they could."

It is statements of this sort that confuse me, because once again it seems as if we are very much on the same side. Sort of like when a husband and wife are arguing about paying the bills. They both agree the bills should be paid. They simply disagree about the order in which they should be paid.

I remember your saying that it would be fine to get a four or five hundred mile range if that meant that acceleration to 60 MPH would only be 6.0 seconds instead of approaching 'Supercar' status. All I have been pointing out is that: 1) Even with the drivetrain of the Tesla Model S P85D, if the acceleration were limited to that 0-60 quickness, you would still not achieve a 400 mile range as a result; 2) That the maximum possible range is determined by the amount of battery capacity available; and 3) The way someone drives determines the usage of that battery capacity to get either more or less range in the end.

Perhaps I misunderstood, or perhaps you changed that position at some point.

Either way, I apologize for my own lack of attention.

Model ☰ | 30 November, 2014

@Grinnin'
Tesla HQ has explained the delayed availability of the S85D compared to the P85D as due to a need to complete testing of the S85D motor. Either they are blowing smoke, or it's a different motor than the front motor of the P85D.

I smell smoke ;)

Not that I say they don't need to test the motor in "none-P" configuration, even after minor adjustments. So test does not say it's a different motor, just that it is modified, and that is known.

But the delivery pattern is the same at it has always been from Tesla - first the most expensive cars, then the less expensive cars. So it was when the Model S started deliveries in 2012, when they got to Europa in 2013 (and probably other markets) and now with the D in 2014.

Brian H | 30 November, 2014

It's in the nature of larger batteries to be able to a)output faster and b)output longer. You could artificially restrain a) to "save" charge for b), but that's just a fudge.

Grinnin'.VA | 1 December, 2014

@ Bikezion | November 29, 2014

Grinnin;
Take a small block of wood, put it under the accelerator pedal of your model S. There.

Either you don't understand my point or you're intentionally misrepresenting it. Tesla's engineers have far more options than just changing the accelerator mapping.

Red Sage ca us | November 29, 2014

I'm just trying my absolute best to make sure that our discussions are as complete as possible, to ensure our communication in this medium is as thoroughly comprehensive as we can manage.

Good idea.

Perhaps you have changed your opinion at some point.

Undoubtedly some of my opinions have changed as I have found new information relevant to the issues.

You followed that with, "I believe you are one of the 'performance car' enthusiasts who has said that you don't want Tesla to do such a thing even if they could."

It is statements of this sort that confuse me, ...

My use of "I believe you are one ..." is a clear invitation for you to correct any misunderstanding. Yet you react saying it "confuse me". Well, please correct my misunderstanding if you are not a "'performance car' enthusiasts who has said that you don't want Tesla to" make a car with a 6.0 sec 0-60 time with an increased range, assuming that Tesla could do so.

@Model ☰ | November 30, 2014

@Grinnin'
Tesla HQ has explained the delayed availability of the S85D compared to the P85D as due to a need to complete testing of the S85D motor. Either they are blowing smoke, or it's a different motor than the front motor of the P85D.

I smell smoke ;)

If the front motors for the P85D and the S85D are the same, Tesla HQ flat lied to me. I was indeed told that they are different motors.

But the delivery pattern is the same at it has always been from Tesla - first the most expensive cars, then the less expensive cars.

I don't recall any other instance in which 'non-P' orders were scheduled to be delivered in the U.S. about three months after 'P' orders confirmed on the same day. Furthermore, I discussed Tesla's 'priority production scheduling' for 'P' orders with Tesla HQ. I was told that this priority never delayed 'non-P' orders more than a couple of weeks or so. IMO, 3 months is a lot more than a couple of weeks.

Ron :(

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