The 2012 Tesla Model S all-electric sport sedan is now in a race with time.

The first production Model S was delivered in June, and Tesla has cautiously been ramping up production numbers while trying to keep initial quality high.

But the company has said repeatedly it will sell 5,000 of its new electric car by the end of this year, and indeed, its cashflow needs may require that volume to be delivered.

Tesla news often seems to come first from the personal Twitter account of CEO Elon Musk.

So it was with a message late last night, in which Musk tweeted, "Tesla made 100 vehicle bodies this week for the first time. Really proud of the team!"

Accompanying the message was a photo of a partial aluminum frame that Musk identified as "S/N 396," or serial number 396--indicating that almost 400 production bodies have now been assembled.

[UPDATE: In SEC paperwork filed on September 25, Tesla Motors stated, "As of September 23, 2012, we have produced a total of 255 Model S vehicles, including 77 Model S vehicles produced during the week ended September 23, 2012. " That number presumably refers to completed vehicles, not body shells.]

[EDITOR'S NOTE: Five days after this article ran on September 17, we were contacted by Christina Ra of Tesla Motors, who said the number of 400 bodies built was inaccurate. She would not provide any information to back up this claim, beyond saying that the serial number is not indicative in this case. In the absence of actual facts, you may draw your own conclusions.]

Separately, Musk said four days ago in a Fox Business video interview that the company was likely to build 80 completed cars this week, after assembling 40 last week.

In the same interview, Musk predicted a "tsunami of hurt" coming for investors that have shorted the stock of Tesla Motors [NSDQ:TSLA], of whom there are substantial numbers.

When we drove early-production Model S cars in mid-July, the serial numbers of the four different models were 106, 108, 111, and 116.

Eight weeks later, the company has built 280 more cars.

To hit its goal of 5,000 sales, the company likely needs to build something like 5,500 cars.

Model S vehicles are personally delivered to a location of the buyer's choice, so the company's "pipeline" holds less inventory than for companies that offer conventional dealer distribution.

To build 5,200 more cars in the 14 weeks between now and Christmas, Tesla Motors will have to hit a production rate around 400 cars a week, or the 80 cars a day Musk has mentioned in the past. That's five times the current rate.

Thus far, and unlike startup Fisker Automotive, Tesla has not had any major quality flaws reported in the media.

Will the company achieve its goal of 5,000 deliveries by December 31?

Leave us your thoughts in the Comments below.

[hat tip: Brian Henderson]


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