Here’s the skinny on the 510bhp turbo unit that’ll power Merc’s upcoming ‘GT’ sports car
Wave goodbye to the era of natural aspiration. AMG’s new Porsche 911-fighter (pictured in teaser-y form above) will be powered by an all-new 4.0-litre biturbo V8 when it arrives later this year.
Which, in good news for people with hyper-sensitive ears but bad news for the rest of us, means AMG’s signature 6.2-litre atmospheric V8 - badged 6.3 for historical reasons - will move aside for this smaller capacity, turbocharged unit. At a technical briefing at AMG’s Affalterbach home Christian Enderle, Mercedes-AMG’s head of powertrains, outlined the new unit, which will first feature in the firm’s new two-seater GT.
After years of unrepentant focus on the naturally aspirated 6.2-litre unit, AMG’s first engine to be wholly developed in-house, the unhinged hot rod division has had to bow to the ever-tightening legislation regarding economy and emissions. Still, as any good German engineer would, AMG’s people simply saw demand for greater efficiency as a means to achieve more performance.
From the outset, then, the 4.0-litre V8 biturbo unit offers up 510bhp at 6,250rpm and 649Nm of torque from just 1,750rpm. Plenty then, and this is just the start.
Helping achieve that is a pair of turbos nestling in the curiously named ‘hot V’ between the cylinders. The result? A quicker, easier path for the turbochargers to do their stuff, AMG’s piezo direct injection system allowing as many as seven squirts of fuel in any single combustion cycle. AMG promises a soundtrack befitting of a proper AMG, too.
Enderle and his colleagues smirk at the idea that the V8’s soundtrack might need to be ‘topped up’ through the car’s speakers, something to which their rivals over at BMW’s M division have resorted. No, it’s all proper heavy metal engineering at AMG: sand casting, unique zirconium-infused alloys in the cylinder head, and polished, patented mirror-finish ‘Nanoslide’ finishes in the cylinders that you could see your face in, assuming you could fit it in the engine’s bore.
Lighter internals make for faster responses, AMG’s engineers promising that, along with a rousing soundtrack, there’ll be no noticeable lag from the turbos. Friction losses have been minimised, thanks in part to AMG’s F1 lubricant partner Petronas, the Affalterbach operation in weekly contact with its AMG High Performance Powertrains colleagues at its Brixworth plant in Northamptonshire.
Dry-sump lubrication gives a low centre of gravity for improved dynamic response, with a new ram-air cooling effect creating a ‘cold air shower’ over the top of the V8. The result, says AMG, will be all the performance we’ve come to expect from the ballistic tuning division, but with economy and emissions that Enderles promises will ‘astonish’ us. We’ll find out later this year…