Tesla CEO Elon Musk has some deflating news for Tesla faithful eager to savor the delights of the new Tesla Roadster 2020 all-electric battery-powered four-seat sports car -- including flying.

Musk last week made a really big deal about the upcoming Roadster 2020, revealing eye-popping specs and delivery promises. His most fantastic promise is this really fast car (0 to 97 km/h in just 1.9 seconds) will also come with 10 “cold” rocket engines for more maneuverability.

These rocket engines might even allow Roadster 2020 to fly, claimed Musk.

Asked over the weekend when people might expect to see a hovering Roadster, Musk matter-of-factly tweeted, “Maybe end of next year.”

Last week, Musk initially said these cold thrusters will “dramatically improve acceleration, top speed, braking and cornering.” And he later got everyone’s attention by saying the rocket engines will “maybe even allow a Tesla (Roadster 2020) to fly.”

By fly, he meant the Roadster being able to hover over the ground. While not flying in the sense we normally associate with the word, having a car hover will be a fantastic feat no one’s done before.

This promise, however, came along with some deflating news. When he first unveiled the new Tesla Roadster in November 2017, Musk set a timeline to production for 2020. Musk’s announcement the new Roadster will be able to hover by late 2020 is being taken by some analysts to mean that production of the car has slipped to that time frame.

Confirming this delay is a statement Musk made saying the release of the new Tesla Roadster isn’t a priority.

While a hovering Roadster might have to wait until 2021, your basic Roadster 2020 remains a speed demon.

The Roadster’s 10 cold gas thrusters will be mounted on a “SpaceX package” Roadster capable of rocketing from 0 to 97 km/h (0 to 60 mph) in 1.9 seconds. This feat will make this car the fastest street legal production car in the world. Range will come to 620 miles.

Tesla has been taking reservations for the $200,000 base version (with a $50,000 deposit) since late 2017. The first 1,000 Roadsters in the Founders Series will retail at an eye-popping $250,000.

Jamming these cold thrust engines into a Roadster’s interior is going to take some doing. Musk has said the SpaceX package will mean removing the backseat of the Roadster so the thruster’s air tank and compressor can fit inside the interior.

Each of the 10 cold gas thrusters will eject compressed air through propelling nozzles to generate a cold jet thrust. The air tanks powering the thrusters are based on the "composite overwrapped pressure vessel" (COPV) also used in the Falcon 9 and Falcon Heavy rockets.

The thrusters will be used to improve cornering, acceleration, top speed, and braking. Working pressure will come to 10,000 psi (700 bar).