New Merc S63 AMG - latest pics

Mercedes has released new pictures of its retro S63 AMG concept car, which is being used as a showcase for its new twin-turbo 5.5-litre V8 engine. The engine will first make production in the revised Mercedes S63 AMG, due on sale this summer.

The stripped-out concept decked out in the livery of Mercedes’ 1971 300SEL AMG racing car. That car was powered by a 6.8-litre AMG engine. The new concept features several design touches that will make it into this summer’s revised S63 AMG, including wider wheel arches and sills.

See the latest Mercedes S63 AMG concept pics

Despite having a smaller capacity than the 6.2-litre V8 it replaces, the new unit, codenamed M157, produces more power and more torque and promises improved fuel efficiency.

A total of 537bhp is produced at 5500rpm (versus 518bhp at 6800rpm in the 6.2 V8) and 590lb ft of torque is also on offer between 2000 and 4500rpm, which is considerably more than the 464lb ft at 5200rpm produced in the current engine.

A 563bhp, 664lb ft version of the engine will also be available as part of a performance package upgrade on the S63 AMG.

The engine weighs 204kg, the twin turbochargers are provided by Garrett and the engine will be mated to Mercedes’ seven-speed MCT transmission, which is also found in the E63 AMG. Fuel consumption in the 5.5 V8 has been improved to 26.9mpg from 19.6mpg in the outgoing 6.2 V8.

The new unit is based on an upcoming Mercedes twin-turbo 4.6-litre V8 engine, which will find its way into the new CLS and S-class models later this year. It’s codenamed M278.

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