Peter Valdes-Dapena, CNN Business

LOS ANGELES — Iron Man star Robert Downey Jr. helped unveil Audi’s upcoming all-electric sports car just before the official kickoff of the Los Angeles Auto Show. The Audi E-Tron GT is expected to go on sale in 2020.

With 590 horsepower, the E-Tron GT will be capable of going from zero to 60 miles an hour in about 2.5 seconds. It’s top speed will be about 149 miles an hour.

The slope-backed four-door shares much of its engineering with the upcoming Porsche Taycan. Porsche and Audi are both subsidiaries of Volkswagen AG and the two brands collaborated on the cars’ fundamental engineering.

Like the Audi E-Tron crossover SUV unveiled in San Francisco in September, the E-Tron GT doesn’t look startlingly different from Audi’s current combustion-powered cars. It’s a little lower and its sides are more sculpted than the similarly shaped Audi A7. It even has a version of Audi’s trademark grill, despite the fact that electric vehicles don’t need nearly as much cooling air as gasoline- or diesel-powered vehicles.

The car unveiled in Los Angeles is technically a concept car, but Audi executives insisted it is very close to the final production version that will go on sale in a couple of years.

Like Tesla’s all-wheel-drive cars, the E-Tron GT is powered by two separate electric motors, one for the front wheels and one for the back. It also has four-wheel steering, enabling tighter cornering.

The E-Tron concept car has a range of just under 250 miles on a full charge according to a standard European driving test, Audi said. With fast charging, the battery will be able to charge up to 80% of that range, or about 200 miles, in 20 minutes. Wireless charging will also be available on the production version, Audi said.

Volkswagen AG has made major commitments to producing electric vehicles. As part of that, Audi has said it will have 12 all-electric cars on the market by 2025. Audi has also said that, by that time, at least a third of its sales will be of autos that are at least partly powered by electricity.