Mercedes AMG GT gets new 503 bhp Twin-Turbo 4.0 litre V8 (video)

Mercedes has revealed the AMG M178 4.9 litre twin-turbo V8 engine with 503bhp and 479lb/ft of torque. Will arrive first in the new AMG GT.

We’ve speculated that the new Mercedes AMG GT – and, for that matter, futures ’63’ AMGs – will get a new twin-turbo V8 to provide the power as Mercedes look to move away from the naturally aspirated 6.2 litre V8 in cars like the SLS. And this is it.

A new 4.0 litre twin-turbo V8 – the M178 engine – has been developed to replace the 6.2 litre V8 and, in initial tune, develops 503 bhp at 6250 rpm and 479lb/ft of torque from just 1750 rpm.

It comes with plenty of technology to yield a lot of power from a relatively small engine with flow-optimised heads, a pair of turbos mounted between the cylinder banks, piezo injection system, dry sump lubrication and Nanoslide friction reducing material.

It adds up to an engine that promises much, even if its initial state of tune falls a long way short of the up to 630 bhp the 6.2 litre V8 delivers. But it seems clear that the 503 bhp the M178 engine offers is just the starting point, and there will be much more to come.

But with twin-turbos and a healthy does of torque from much lower down the rev range, the new 4.0 litre V8 should suit the new AMG GT very well, which is just as well as that is where it will first find a home before being rolled out in other Mercedes AMGs, including the new C63 AMG.