Tesla Motors [NSDQ:TSLA] CEO Elon Musk’s big announcement regarding the “D” has, as we suspected, turned out to be a new dual-motor option for the Model S that provides it with the extra traction of all-wheel drive. And the “something else” Musk also hinted at previously is a new semi-autonomous system dubbed an Autopilot. The system offers a few basic functions at present but it’s upgradable—via software updates—and will offer greater functionality in the future.

But getting back to the dual-motor option, it essentially adds a second electric motor to power the front wheels of the Model S and is being offered across the lineup, meaning a 60D, 85D and high-performance P85D. The 60D and 85D feature identical motors front and rear to give a combined output of 376 horsepower. The P85D’s rear motor is rated at 470 hp and the front at 221 hp, giving the car a combined output of 691 hp!

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Incredibly, the P85D is claimed to accelerate from 0-60 mph in just 3.2 seconds, rivaling the times of many supercars and outmatching virtually all sedans on the market—including perhaps the world's most powerful sedan, the 707-hp 2015 Dodge Charger SRT Hellcat.

The dual-motor option also increases the driving range of the Model S by about 10 miles versus the current single-motor, rear-wheel-drive models, allowing the 60D to travel about 225 miles at an average 65 mph, the 85D about 295 miles and the P85D about 275 miles. This is due to efficiencies designed into the new system, according to Tesla.

Deliveries of the dual-motor, all-wheel-drive Model S sedans will begin in February, 2015. The cost of the dual-motor option for the 60D and 85D is just $4,000 but for the P85D you’re looking at $14,600, bringing the price tag up to $120,170. Of course, you’re getting supercar performance in a sedan that can seat up to seven.

Tesla Model S Autopilot system

Tesla Model S Autopilot system

As for the Autopilot system, it relies on a forward looking camera, radar, and 360-degree ultrasonic sensors that have recently been added to the Model S and actively monitor the surrounding roadway (they can’t be fitted to older models, unfortunately). Progressive software updates over time will enable sophisticated convenience and safety features that use these sensors to respond to real world conditions. These features will ultimately give Model S self-driving capability on the highway from on-ramp to off-ramp, though there’s been no mention of a timeframe for this. It should be noted that rival automaker Mercedes-Benz already offers such technology.

What the Autopilot system can do at present is read speed-limit signs and adjust the car to the speed on the sign. It can also change lanes when the driver uses the turn signal. Yes, when highway driving, all you have to do is select left or right and the Model S with Autopilot will check for a free spot and slide over. We also hear that the system will be able to automatically park the Model S.

The Autopilot system is included with a Tech Package that costs $4,250.


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