Many Tesla fans and electric-car drivers now know about the Model S P85D, Tesla's all-wheel-drive electric car that's arguably the fastest four-door sedan on the market.

What most of them likely don't know is just what the car's ultimate performance mode, called "Insane," actually feels like.

DON'T MISS: Tesla P85D Destroys Dodge Challenger Hellcat On Dragstrip: Electric Car Thrashes 707-HP Hemi (Video)

Now there's a video out from Drag Times that shows how astoundingly, jaw-dropping, amazingly, startlingly, wildly, incredibly insane the Insane mode actually is.

NOTE: Video is NSFW, has rude words (delivered in tones of shock, horror, awe, amazement, and joy).

With 1.3 million views in three days, the reactions to Drag Times CEO Brooks Weisblat's demonstration of standing-start acceleration pretty much speak for themselves (above).

2014 Tesla Model S P85D, road test, Dec 2014 [photo: David Noland]

2014 Tesla Model S P85D, road test, Dec 2014 [photo: David Noland]

When it was first announced by Tesla CEO Elon Musk, the all-wheel-drive "D" version of the Tesla Model S had been expected as an addition to the lineup.

But the all-out highest-performance model, the P85D, hadn't been.

ALSO SEE: Tesla P85D Top Speed, Performance To Be Boosted In 'Next Few Months'

By modulating power delivery to each of its two electric drive motors, the Tesla can deliver maximum traction every fraction of a section to use all four wheels to propel the car toward the horizon.

Like any electric car, it uses an enormous amount of its limited onboard energy to overcome wind resistance at higher speeds, so it's fastest off the line and up through legal speeds.

Tesla Model S P85D 'Insane' mode acceleration [frame capture from DragTimes video]

Tesla Model S P85D 'Insane' mode acceleration [frame capture from DragTimes video]

But the P85D will run out of range fairly quickly when driven above U.S. legal limits, and it certainly can't cruise at extra-legal speeds for hours as many competing high-performance sports sedans can.

None of which matters a whit to the astounded, wide-eyed, gleeful passengers in the video.

MORE: 2014 Tesla Model S P85D: First Drive Of All-Electric AWD Performance Sedan

Many of the passengers use language that's clearly Not Suitable For Work (NSFW), including a nice, gentle-looking older woman. The little kids probably have the best giggles.

But the most consistent grin is on Weisblat's face, after innocently showing the Insane mode button to the unsuspecting passengers about to be thrown at the landscape ahead.

The last rider's reaction may be the best: "I could do that every day. I need this every day, Brooks--every single day!"

_______________________________________________

Follow GreenCarReports on Facebook, Twitter, and Google+.