The V8 engines have long been a core competence at AMG, the performance brand of Mercedes-Benz. Christian Enderle, Head of Engine and Powertrain Development at Mercedes-AMG: “With the new AMG 4.0-liter V8 biturbo engine, we present a fascinating and powerful sports car engine, which also achieves the next step in efficiency due to numerous measures”.
The new AMG V8 engine has two turbochargers which are not mounted on the outside of the cylinder banks but rather inside the V configuration – experts call it a “hot inside V”.
The advantages of this layout: the eight-cylinder engine has more compact dimensions, which allow the low installation position as well as optimum weight distribution between the front and rear axles. The “hot inside V” also optimizes the supply of fresh air to both exhaust gas turbochargers. Electronically-regulated blow-off valves guarantee an immediate and direct response. The maximum charge pressure is 1.2 bar and the turbochargers can reach a maximum speed of 186,000 rpm. For combustion 2.3 times as many oxygen atoms are pressed into the turbo engine than a naturally aspirated engine.
Air/Fuel mixture preparation is handled by the petrol piezo direct injection system used exclusively by Mercedes. The third generation of the spray-guided combustion process has been developed to meet all future legislative requirements. The 4.0-liter V8 biturbo engine fulfills the Euro 6 emissions standard, including the rules pertaining to maximum particulate emissions that do not come into effect until 2016. A sophisticated engine cooling system ensures high performance at ambitious race-track speeds.
The dry sump lubrication allows the engine to be installed in a low position with a lower center of gravity – ideal for a sports car with high lateral dynamics. As well as the enhanced agility, dry sump lubrication ensures optimum lubrication of the engine through direct oil extraction from the crankcases, even at high cornering speeds.
As a result the M178 (the internal AMG designation) is the world’s first sports car engine with hot inner V and dry sump lubrication. The new AMG V8 with a dry weight of 209 kilogram is the lightest engine in its segment.
As the newest member of the BlueDIRECT engine family, the AMG M178 boasts a power delivery and performance figures on a par with motor racing. It boasts an unmistakable AMG V8 engine sound, along with an immediate response and high pulling power. The torque curve is synonymous with good drivability: the maximum value of 650 Nm is on hand in a wide range from 1,750 to 4,750 revolutions.
The AMG 4.0-liter V8 biturbo engine is made in Affalterbach in accordance with the principle of “one man, one engine”. In the AMG engine workshop, qualified technicians manufacture the high-performance engines by hand to the Mercedes-Benz quality standards. The signature of the respective technician on the AMG engine plate attests to this type of engine production. It guarantees quality and the transfer of technology from the racing series – from Formula 1 and the DTM to the customer sport activities with the SLS AMG GT3.
This “hot inside V” adds a lot of thermal constraints on the cylinder head and surrounding parts as well as for the turbochargers. Additionally, we have seen a lot of thermal issues in the new Formula 1 engines due to the tight space available for the turbocharger. Do you think that AMG engineers have consulted Mercedes-Benz F1 engineers in order to find solutions to the thermal protection issue?