Mercedes’ AMG division unveils new twin-turbo V8

Those obsessed with torque bemoaned Mercedes’ high-revving 6.2-litre V8 when it was launched in 2005, but just as the world has come to accept the naturally aspirated engine, the company has now unveiled a new twin-turbo 5.5-litre V8.

Up to 563bhp – which is the same as the SLS AMG – and 663lb ft, which is much more than the 479lb ft the modern-day Gullwing supercar manages.

The engine is an all-new 5.5-litre V8 (5461cc to be exact) with direct-injection technology, an aluminium crankcase and two turbochargers. In standard tune the engine produces 544bhp at 5500rpm and 590lb ft at 2000-4500rpm. Cough up for the AMG Performance Package (which ups the maximum charge pressure from 1.0 to 1.3 bar) and those figures will increase to 563bhp (at the same 5500rpm) and 663lb ft at 2500-3750rpm.

Of course the new engine is cleaner and more efficient too. Thanks to a seven-speed wet-clutch auto and stop/start tech (which works with the gearbox’s Controlled Efficiency setting) the 5.5-litre engine achieves 26.9mpg and 246g/km CO2 (versus 19.5 and 347g/km for the S63 AMG is replaces), which are reductions of 25% and 28.5% respectively. And that’s despite it besting the S63’s 518bhp and 464lb ft, the latter by quite some margin too.

And it’s faster as well, though we’re talking tenths here – 62mph comes up in 4.5 seconds (4.4 with the Performance Pack) while the outgoing S63 took a yawning 4.6 seconds. The top speed is still limited to 155mph, though again those paying the extra cash for the PP have a higher electronic threshold of 188mph.

Yes, there’s no 55 badging here – the 63 moniker has historical significance for Mercedes. That means from this summer the S63 AMG will be running the new 5.5, and the very first car to receive the engine is an S-class that’s been dressed up to look like the 300 SEL 6.8 AMG. The purple limo gets historically accurate stickers, plus a stripped-out interior (but complete with wood trim inspired by the classic racer), huge 20-inch wheels and tyres, plus a 4.5-inch wider front bumper.

By Ben Pulman