Mercedes-AMG shines spotlight on 375kW GT V8

AMG is claiming the upcoming GT sports coupe will smash out an enormous 375 kW of power from its all-new 4.0-litre twin-turbo V8.

Mercedes-Benz's power-punching offshoot has brimmed the new V8 with technology, including everything from multi-squirt direct injection, a pair of twin-scroll turbochargers and Nanoslide cylinder lining technology.

It has even gone back to its motorsport roots to give it dry-sump lubrication in an effort to pull the GT's centre of gravity down by just 55 mm to help its handling and cornering speed.

The new engine, which will be driven for the first time in the GT in mid September this year, keeps its two turbochargers nestled inside the engine's 90-degree vee to help with throttle response and packaging.

It will reach its peak power figure of 375 kW at 6250 rpm, but might become even better known as a flexible powerhouse, with its 650 Nm of torque arriving at 1750 rpm and plateauing at that level until 4750 rpm.

In spite of all that low-end torque, the engine still spins out to a maximum speed of 7200 rpm.

Designed, developed and built at AMG, the new M178 powerplant is heavily based around the architecture of its own 2.0-litre turbocharged engine, which develops 265 kW and 450 Nm in the A 45 AMG hatch and CLA 45 AMG sedan.

It shares the same 90 mm bore spacing as the four-cylinder and a detuned version of it will find its way into the upcoming C-Class AMG, the C63 AMG.

"V8 engines are an integral part of the AMG philosophy and the brand's commitment to driving performance, AMG Chairman Tobias Moers said yesterday.

The 3982 cc engine will deliver a maximum turbo boost pressure of 1.2 bar and a maximum turbo speed of 186,000 rpm while pushing 2.3 times more oxygen inside the cylinders than a naturally aspirated engine. It also uses an indirect air-to-water intercooler.

The 209 kg motor has a 10.5:1 compression ratio and third-generation direct fuel injection, complete with piezo injectors capable of multiple injections per stroke.

It has an extra 12-litre plastic oil tank inside the engine bay to cater for the dry-sump system, which also includes a suction pump and a pressure pump and circulates nine litres of oil constantly through the engine.

Inside, it uses a pair of zirconium alloy cylinder heads with variable valve timing and lift, while the pistons are forged from aluminium.

It has the same innovative Nanoslide cylinder bore liners that are used in the current Mercedes-Benz Formula One car. Twice as hard as a conventional liner and highly polished, the Nanoslide liner weighs less and takes up less space.

AMG insists the engine will not only be powerful, but economical. It already meets the 2016 Euro VI emissions standards and AMG insists it will post fuel consumption figures below 10L/100km on the NEDC cycle.