I did a test ride of a P85D last night. It was breathtaking. The car explodes (silently) of course like a rocket. It feel much, much faster than a regular P85. Here's the test ride I took: https://www.youtube.com/watch?v=Qm5CQZalLg8

It's difficult to explain in just words how fast 3.2 seconds is and I had a difficult time grasping it myself until I actually sat in a Tesla P85D and experienced it going from 0-60 in a blazing quick three seconds. It felt like a completely different (and much quicker) car than the previous single-motor P85. The car accelerates so quickly with so much force that I found myself in disbelief and awe. Tesla truly engineered an amazing new version of the Model S.

This new dual-motor version of the Model S is available to order in the performance version and will be available in the 60kwh and 85kwh version vehicles in February. Overall, having an AWD dual-motor version expands the appeal of the Model S to more market segments, especially those in colder areas. And the addition of a dual-motor performance version catapults the P85D into the realm of a true super car.

Also in an unexpected and shocking move, Elon Musk announced Tesla's Autopilot hardware at last night's event. Most people were expecting some trivial driver assist features like lane departure warning and adaptive cruise control. Further, in previous interviews Elon had alluded to Autopilot being ready by the end of 2015. But in last night's announcement, Elon outlined a 4-part Autopilot system that would allow for driving to become increasingly autonomous over time.

The Autopilot system comprises of cameras, radar, sonar, and gps/navigation integration. At first, the system will allow for drivers to use Autopilot to keep in one's lane and to slow down or speed up depending on objects in front. Over time with software updates, Autopilot will allow for full autonomous driving from freeway on-ramp to freeway off-ramp. Autopilot will also allow for the car to be able to park itself or even for it to be summoned by the owner.

In my test ride last night in a P85D, there was a brief section where we were able to see the car drive itself autonomously. The car followed the roads as it curved and also adjusted for speed limits. It also managed to change lanes by the driver just turning the signal light on. It was quite impressive.

What's further impressive is that Autopilot is a feature that is now added on to the Tech Package at an additional minimal cost (new Tech package costs $4250 vs old Tech package costed $3750). This is a great deal and will make the car even more appealing to more people.

Here's the official video from last night's presentation by Elon regarding dual-motor and Autopilot. The Autopilot description is especially interesting. https://www.youtube.com/watch?v=FZ6lZJWL_Xk

(ps, for those interested I curate a weekly email newsletter called Tesla Weekly, http://teslaweekly.com, with the latest news regarding Tesla)

Thank you for your review. Just makes me want to own a Tesla now.. This is so exciting!

So to compare how fast a S P85D is... Lamborghini Veneno is 2.8s 0-60 costs $4.5m. Porsche GT3 is 3.3s 0-60 costs $130k

The S P85D is a sedan family car with the power of a race car.. 2 electric motors powering an AWD setup. New models go 10 miles further then old models with a single electric motor. That's Innovation to be excited over.

Well, it has the low-speed torque of a race car. 0-60 is a stat that electric cars are uniquely good at. It's not the only stat that matters to race cars.

It also has an absurdly low center of gravity due to the batteries being mounted along the entire bottom of the car.

Corvette Z06 can do 0-60 in ~3s for $80k

The P85D will probably be around $130K also. The current P85+ is around that already.

I ride a GSXR 600 and it has the same 3.2 sec 0-60. It still rattles me every time I push it that fast. I'm having trouble wrapping my mind around how they can replicate that experience inside of an _electric_ car. Can't wait to test drive it :)

Yeah, first time I hit the powerband on the sportbike I almost fell off it. I remember it very well, even though it was years ago. The power/weight ratio is staggering.

> I'm having trouble wrapping my mind around how they can replicate that experience inside of an _electric_ car.

Your gixxer (and my poor, now deceased, ninja) could only do it because these are vehicles not much heavier than 2x the weight of the owner. Insane power/weight ratio will do that for you.

But their engines, like any internal combustion engine, suck at low speed. Have you seen the dyno curve for torque? It's really low at first, and only then starts climbing, and climbing, and climbing.

An electric engine gives you maximum torque at any speed. Now imagine that on your sportbike. ;) When technology is more mature, all electric engines will run circles around internal combustion, on the 0-60 track.

Electric vehicles' strong suit has always been high acceleration. I know a motorcycle fan who tried out a high-powered electric cycle, and even with some serious power limiters it was still much more of a kick when accelerating up to high speed than anything gas-powered could pull off.

Bike vs Car acceleration feels different on the driver but I echo your views. Cars have the advantage of back support which essentially feels like a plane taking off - pinned & safe. And if you have a bucket seat then it's more fun round the corners while the adrenaline rushes. The P85D would be a great track car!

All the latest super cars breaking records using electric motors. The fastest car Car & Driver ever tested is the 2015 Porsche 918 Spyder — 0-60 in 2.2s. A hybrid, just like the new P1 from Mclaren.

I thought you were talking about another car. Then I reread he model number. Now we all have a (very telling) comparison point.

Come on, I meant about communicating what kind of acceleration you'd experience. I rarely bump into sports car, but I've seen a lot of GSXR-class bikes.

Sorry, in that case! I made a poor assumption :-/

You're right, it sounds like a reasonable frame of reference.

Classic internet. Have a nice day :)

They did a good job with the lighting effects. Especially in the tunnel it seems a lot faster than it actually is I think.

With the car getting further away, the speed sensation diminishes. The lighting effects help with the compensation.

That acceleration is a bit like a roller coaster that you can drive.

Truly not far from it... 0 - 60 in 3.2s = .85g

That looks amazing! But, if someone "gets funny" and paints a 25mph sign as 55, then what? Any countermeasures for this?

Someone should try making a sign that says

    () { :; }; /usr/bin/media_play 'https://www.youtube.com/watch?v=dQw4w9WgXcQ'

I had a Tom Tom about 5 years ago that knew the speed limit on major roads. I'd imagine Google et. al. are collecting that data even if it's not publicly available in their mapping APIs yet.

How do you think that they can predict route times? It might not be part of the UI, but I'd wager they've had the data for a long time. The accuracy of the data, though, might be a reason that they don't present any of that data as fact.

Wait, what? Every navigation system I ever used showed the speed limit and was capable of giving a warning if you go to fast. And it is pretty accurate, usually maybe plus or minus a second of passing the sign. Road works or just recently altered speed limits will of course yield no or false displays but fourtunatly road works are obvious and they don't change speed limits every other day.

Google doesn't show it. I don't know if they are afraid of lawsuits or if they feel it to be a distraction or anything like that.

> I'd imagine Google et. al. are collecting that data [...]

They are. All phones who have Google Maps installed, and have enabled reporting (anonymous) position data (might be default on some phones) are helping Google both see if there's a traffic jam somewhere, and see what the actual driving speeds on the roads are (by sampling at a certain interval and seeing distance traveled over time).

I happily contribute to this, I think it's a great idea to crowd-source traffic data. I do hope Google makes the data publicly available though.

Waze[1] is all based on users' feedback and has been acquired by Google in 2013, so I think we'll see this more and more..

[1]http://en.wikipedia.org/wiki/Waze

Nokia maps did this. Also you could set a speed limit warning at your preferred limit, usually about 10% above for me. It was quite handy on long drives.

The sort of AI necessary to drive a car is not like conventional programming code. You already can not simply blindly trust a sign. As a human you're so used to converting bad signs into something meaningful or ignoring them, but it's just part of the base problem of driving, not some sort of special problem. The sign is merely one of a constellation of inputs already coming in, already contradictory (speed limit is 55, traffic is driving 65, road conditions should only be permitting about 35, what do you do? etc.).

Oops, I read this backwards.

The car should use the minimum speed limit from its set of stored speed limit signs, rules about local roads, and what it sees. If the car sees a speed limit sign that's "too high," it should call back to the mothership for a proper investigation (by the autodrive maker or the local police or both).

OLD POST (where I got your situation reversed):

It _should_ drop to 25 mph, because maybe someone in authority put a real 25 mph sign there. Then they should investigate who did that.

The countermeasure would be to take over the wheel.

The eventual countermeasure would be to have the speed limit sign broadcast its number over radiowaves, which is of course still something people can mess with, but requires a higher bar than a can of glue.

What would a human do if they saw a 25mph changed to say 55mph?

"That doesn't seem right", probably.

We have a 55 mph zone near our house that anyone not from the area seems unable to believe (as it's a narrow, fairly winding two-lane road) and you get stuck behind them puttering along at 35 for a few miles.

You're driving along a road. The signs all say that the limit is 55mph. You pass a sign that says "55mph ends." Now what?

[Note: The route to a friends house years ago did exactly this as you got away from developed areas.]

The UK's rules for what to do when there isn't a sign: https://www.gov.uk/speed-limits

Of course there's the unofficial and regularly observed "I think this is 60, but I can't see (or have no idea what is) a NSL sign so I'm going to do 45-50 to be safe"

It varies state by state and can depend on what kind of road you are on. Most states define a default speed limit for roads and highways.

Most states have rules such as: "35mph unless otherwise posted".

If you see a crazy curve ahead, you would slow down

I like that. Let the robots determine the appropriate speed limits in real time.

In Oregon the basic speed rule says that if you are going around a curve too fast to be able to stop for someone laying in the road, you are going too fast no matter what the signs say.

Maybe signs of the future should also have a QR code next to them for the real speed, just in case someone modifies the painted one. If they mess with the QR code too, then it should give a warning or something.

Sign the Speed Limit tangled with the GPS coordinates of the sign with a private key of the state. Place both the signature, GPS coordinates, and speed limit in the QR code.

Yeah, in the future the number visible on the sign will be just a courtesy to humans. The authoritative piece of info will be electronic.

A similar situation that impacts humans is someone getting funny and removing a stop sign. I guess the traditional countermeasure is to restore the sign.