Tesla Model S gets AWD for “insane” speed and a range boost – and autopilot too

When Elon Musk tweeted about “unveiling the D and something else,” it didn’t take the internet long to figure out that D stood for dual motor – or all-wheel-drive – and the something else would be related to driver assistance features. That did not take anything away from the truly impressive reveal of Tesla’s latest technology.

All-wheel-drive is a whole different beast with electric motors

A gasoline vehicle with AWD is more secure in slippery conditions than its two-wheel-drive counterparts, and generally offers improved performance at the expense of fuel economy.

Electric motors are a different story entirely, as evidenced by Thursday night’s reveal of Tesla’s AWD variant of the Model S sedan. Electric motors are more efficient at lower loads, so spreading the demand across two motors means each gets an efficiency boost. A dual-motor setup also can provide an impressive power boost, so long as the battery can supply the necessary electrons.

So how good is the now top-of-the-line Tesla Model S P85D? Scary good. “Insane” good, to quote the alleged new third driving mode of the vehicle. “Like having your own personal roller coaster,” in the words of Musk.

A Model S P85 runs the 0-60 mph sprint in 4.4 seconds. The P85D reduces that time to an incredible 3.2 seconds, on par with some of the world’s best sports cars. It can make the quarter mile run in just 11.8 seconds. New top speed is 155 mph, up from the previous 130 mph.

The best part? Range is boosted from 265 to a claimed 275 miles.

The P85D adds a 221-hp motor to the front axle, bringing the car’s total output to 691 hp with 687 lb-ft of instantly available torque. The additional front motor brings weight balance to a perfect 50:50. The system adds nearly 300 pounds of weight, yet efficiency still gets a significant increase thanks to the properties of electric motors.

What about the other Model S variants?

The all-wheel-drive isn’t just coming to the P85 version (it will be available in December). The 60-kWh Model S and base 85-kWh model both will come with the option of the D system for an additional $4,000 starting in February. The new P85D will start around $120,000.

The non-performance Model S versions will get increased range to 225 and 295 miles for the 60-kWh and 85-kWh versions, respectively, up from 208 and 265 miles. The numbers come from Tesla's estimates at 65 mph, but it is worth pointing out that those estimates correlated closely with EPA-rated range on the single-motor models thanks to the car's nearly identical efficiency in city and highway driving.

The reason for the extra jump in range on the base models? They both get 188-hp motors in the front and rear for a total 376 horsepower, which provides an even greater efficiency benefit while still shaving 0.2 seconds of the 0-60 time of each model to 5.7 and 5.2 seconds, respectively.

Expect a high percentage of customers to opt for all-wheel-drive, which will boost Tesla’s margins, lower costs, and make a whole lot of customers very happy. Not to mention the fact that the AWD system opens up Model S sales to even the snowiest regions of the world.

Oh, and that autopilot thing

Not to be overlooked in the glitzy event on Thursday night is the official announcement of Tesla’s autopilot system, which has been hinted at recently.

New Tesla Model S sedans come fitted with 12 sensors to “see” the car’s surroundings. Four new systems work together to enable an impressively high level of autonomy, especially for a car that had no driver-assist features a month ago. Forward looking radar, a frontal camera, long-range sonar, and navigation integration combine to provide capabilities like active emergency braking, speed limit monitoring, automated parking, and a unique feature not seen on any other production car today: the car’s ability to change lanes on its own when the driver flips the turn signal.

The new driver-assist features are the first step toward a full autopilot, and render any previous (valid) criticisms of Tesla’s lack of active safety features meaningless. The automaker has now effectively caught up to most state-of-the-art systems in production today, though it remains to be seen how well the new features work in practice.

All in all, it was a great day for Tesla Motors. Musk and his crew lived up to the hype as usual, and the new features are sure to give Model S sales a boost. Now I just have to find a test drive event for that P85D...