It's a typically warm fall night in Los Angeles, and just after sunset Elon Musk takes the wraps off "the D." This isn't a lewd joke much of the internet imagined: it's the company's new dual-motor, all-wheel-drive version of its Model S sedan, one that promises faster acceleration, and better performance in inclement weather — one of the S' biggest weaknesses. And as Musk would like everybody to know, it's fast. Really fast.

"We're able to improve everything about the car," Musk says after summoning the car's chassis from beneath the stage while thumping music flows out over a large crowd of people who have spent the past hour sipping free drinks.

For a price, the new models of the S will get a "D" on the end. It's not just a badge, but a new system that puts a motor in the front as well as the back of the vehicle. There will be three configurations: the 60D and the 85D, along with a top of the line P85D. The P85D starts going out to buyers in December, with the 60D and lower-end 85D going out in February. Musk did not talk specifics on price, but it's not cheap. Tesla says the base price of the P85D is $120,170, a $14,600 premium as part of an options package from the standard P85 model.

The lack of all-wheel drive has been a shortcoming for the Model S since the first cars rolled off the production line in 2012, with Tesla opting to make it rear-wheel drive instead. That's common among performance cars, but has also left the car lacking compared to competing luxury vehicles from Audi, BMW, Mercedes, and others — particularly in colder climates.

The big question is how the new configuration affects both the car's range, as well as its handling. Today, ahead of a launch for the D, Musk told USA Today the new configuration would up that range by an extra 10 miles per charge, and bring a 0 to 60 time to just 3.2 seconds on the performance model.

Along with the change to the motor configuration, Tesla's added new safety features that help its S models do certain things on the road without driver intervention. It's using cameras and other sensors, something the company has been installing on all new Model S vehicles produced over the past month to conform with European safety regulations. It allows the car to look for objects — including other cars — as well as road lines. That's not a new thing in the auto industry, but an important step in getting cars to be completely autonomous, something Musk has said is still 5 to 6 years away from being a reality.

The system employs an array of different systems, including forward-looking radar, a camera with image recognition, as well as 360 degree sonar. Musk referred to the system as "autopilot" — a term he's used before — saying that the company would be pushing this to see what it could do in terms of hardware as well as with regulations. That gives it lane control, active emergency braking, and self parking (including automatic parallel parking).

Self-driving technologies that do more than just keep the car from drifting out of lanes and hitting objects are the next logical step, promising to increase safety and allow drivers to essentially become just another passenger. Computer-controlled cars also promise to react to things faster, and could open up certain sections of roadways to higher speeds given the extra reaction time — speeding up long distance car travel.

Tesla is far from alone in that pursuit. Audi, BMW, Toyota, and others are all developing self-driving technologies, with many using California as a testbed. Last month the state began issuing permits for limited testing on self-driving vehicles on state roads. Tesla is not part of that group yet, but is promising drivers of today something they'd actually want to control.

"This car is nuts," Musk told an excited crowd filled with Tesla owners. "It's like taking off from a carrier deck. It's bananas. It's like having your own personal roller coaster that you can use at any time."