"We haven't decided on a name at this stage," K llenius says. Moers says it takes a long time to come up with an inspiring name, and a short list doesn't even exist at this point. It could remain nameless for the rest of the year. "It is not R50, period," he says of reports speculating that as the name.

In the interim, it's code-named Project One and refers to a two-seat, mid-engine, all-wheel-drive supercar with a modified version of the hybrid engine used for Formula 1. The V-6 drives the rear wheels, and a pair of electric motors will send power to the front axle. All that power will propel a lightweight vehicle with a carbon-fiber body. It could weigh in as little as 2,200 pounds.

"It's almost like a research vehicle put on the road for an exclusive group of customers," K llenius says.

Even though the price tag will be more than $2.1 million, Mercedes has more than 300 names on a list of interested customers. Would-be buyers started contacting dealers before the Paris auto show in September 2016 when the automaker confirmed the car was in the works. The trick is to figure out who gets them and how many will go to each region of the world. He would not say how many will be allocated to the U.S.

For sure on the list is Formula 1 driver Lewis Hamilton. He's also helping the team with development and will do test driving later this year when there are drivable prototypes. Former teammate Nico Rosberg could also buy one, Moers says.

In terms of development, AMG is finalizing the digital process. "We pulled it out of styling," Moers says. "Design is so far done. Now we are working on details."

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The challenges include retuning the engine, developing a suitable gearbox, and integrating electrical systems. Adapting the gearbox is going well. "I think we have a proper solution now," Moers says. The team still has the challenge of getting a Formula 1 engine running in street-legal mode, but that work is also proceeding nicely, as is the integration work.

Powertrain engineering is being done in Brixworth, U.K., and vehicle engineering work is being done by AMG in Affalterbach, Germany. A number of suppliers are doing the carbon-fiber body. It's still being decided where final assembly will be done, Moers says.

And the automaker must also debate whether to give the electric car the EQ sub-brand name. EQ is a new brand within Mercedes that will include 10 electric vehicles of all sizes and body styles by 2025, starting with an SUV in two years. "It's a unique vehicle in its own right," K llenius says.