Mercedes-Benz has confirmed that its new C63 AMG will be powered by a version of the M178 twin-turbocharged 4.0-liter V-8 debuting in the 2016 Mercedes-AMG GT sports car, and that in the C-Class-based sledgehammer the engine will deliver up to 503 horsepower and 516 pound-feet of torque. For those at home counting, the hp figure matches the output of the more potent GT S sports car but the torque figure is actually 37 lb-ft higher!

This output will likely be reserved for a new C63 AMG S model, with the stock C63 AMG previously reported to be delivering about 470 hp. By comparison, the 2015 BMW M3 is rated at just 425 hp while the 2015 Lexus RC F makes do with 467 hp.

Rear-wheel drive and a seven-speed dual-clutch transmission are expected to be standard across the new C63 AMG range. And once again there will be sedan, wagon and coupe bodystyles. We’ve also been told that an even more potent Black Series model is planned.

But the story doesn’t end there. In addition to class-leading output, the new C63 AMG is also promised to have the best fuel economy in the segment. Mercedes says the engine will be good for 28.6 mpg on the European combined cycle, although it should be noted that EPA-rated fuel economy tends to be lower than the European figures.

A debut of the new C63 AMG is scheduled to take place later this year, either at the 2014 Paris Auto Show on October 2 or at the 2014 Los Angeles Auto Show the following month.

"The AMG V-8 biturbo engine mesmerizes not only with maximum power and torque, but also with the absolute best fuel economy in the comparative segment,“ AMG chief Tobias Moers said in a statement. "It goes without saying that the successor to the current C63 AMG will again be powered by an eight-cylinder engine—we owe that to our loyal fans, plain and simple."


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