Mercedes-Benz M176/M177/M178
Overview
Manufacturer	Mercedes-AMG
Production	2015–present
Layout
Configuration	90° V8
Displacement	4.0 L; 243.0 cu in (3,982 cc)
Cylinder bore	83 mm (3.27 in)
Piston stroke	92 mm (3.62 in)
Cylinder block material	Cast-aluminium, closed deck
Valvetrain	DOHC 4 valves x cyl.
Compression ratio	10.5:1
RPM range
Max. engine speed	7,000 rpm
Combustion
Supercharger	BorgWarner's e-Booster (EQ Boost; 2019—present)
Turbocharger	BorgWarner Twin-turbos
Fuel system	Direct injection
Fuel type	Gasoline
Oil system	M176 and M177: Wet sump M178: Dry sump
Cooling system	Water-cooled
Output
Power output	340–551.5 kW (462–750 PS; 456–740 hp)
Torque output	600–900 N⋅m (443–664 lb⋅ft)
Dimensions
Dry weight	209 kg (461 lb)
Chronology
Predecessor	Mercedes-Benz M278 / M157 engine (4.7 & 5.5L) Mercedes-Benz M152 engine Mercedes-Benz M156 engine

The M176/M177/M178 is a petrol V8 engine range designed by Mercedes-AMG, replacing the M278 and M157 engines, and is based on the M133 engine.^[1]

The engine has two BorgWarner turbochargers positioned between the two cylinder heads in a "hot-V" configuration. The fuel injection system uses Bosch's new piezo-electric direct fuel injectors that deliver five squirts of fuel per combustion cycle.^[2]

The M176 engines are mostly assembled by machine with some components assembled by technicians at Untertürkheim manufacturing centre outside Stuttgart. The M177 and M178 are individually assembled by the technicians in "one man, one engine" principle at the AMG manufacturing centre in Affalterbach.^[3]

M176

The M176 version debuted in 2015 for the Mercedes-Benz G 500/G 550 and G 500 4x4². In 2019, M176 was equipped with EQ Boost mild hybrid 48V electrical system, producing additional output 16 kW (22 PS) and 250 N⋅m (184 lb⋅ft) of torque.^[4] This mild hybrid system was fitted to GLE 580 4MATIC and GLS 580 4MATIC. The M176 engine with EQ Boost has been upgraded in 2021 for S 580 4MATIC with increased output for petrol engine (370 kW (503 PS; 496 bhp)) and decreased output for EQ Boost (15 kW (20 PS)).

Applications

M177

The M177 was the first variation released in the Mercedes-AMG C63.^[5] In contrast to the M178, this version of the engine uses wet-sump lubrication. In the C63 and GLC63 applications, the turbos are single-scrolled, whereas in E63 and S63 are twin-scrolled and different exhaust manifold. The twin-scroll application also features cylinder deactivation.^[6]

As part of the agreement with Mercedes-AMG since 2013, Aston Martin installs the M177 engines in the DB11 V8 and DB11 Volante (2017–), Vantage (2018–), DBX (2021–) and DB12 (2023–).^{[7][8][9][10]}

In late 2019, the 48V system used in the M176 was added to the M177 engines for extra performance, improved fuel consumption, and reduced emission output.^[11]

Applications

M178

The M178 is the second variation in the family, geared toward higher performance and motorsport. The 340 and 375 kW (462 and 510 PS; 456 and 503 hp) versions were introduced in Mercedes-AMG GT (C190). The power has been upgraded several times. Brabus offers PowerXtra B40S-800, a performance upgrade kit for AMG GT.^[12] The kit increases the output to 588 kW (799 PS; 789 hp) at 6,500 rpm and 1,000 N⋅m (738 lb⋅ft) at 1,750-4,500 rpm.

Specifications

• Cylinder arrangement V8
• Cylinder angle 90°
• Cylinder block alloy Cast aluminium, closed deck
• Cylinder head alloy Cast aluminium, zirconium alloy
• Valves per cylinder 4 (DOHC)
• Variable valve timing Camshaft adjustment on both the inlet and outlet side
• Displacement 3,982 cc (4.0 L; 243.0 cu in)
• Bore x stroke 83 mm × 92 mm (3.27 in × 3.62 in)
• Cylinder spacing 90 mm (3.54 in)
• Compression ratio 10.5:1
• Output 375 kW (510 PS; 503 hp) at 6,250 rpm [Output per litre 94.2 kW (128.1 PS; 126.3 hp)]
• Maximum torque 650 N⋅m (479 lb⋅ft) at 1750 – 4750 rpm [Torque per litre 163.2 N⋅m (120.4 lb⋅ft)]
• Maximum engine speed 7,200 rpm
• Maximum charge pressure 1.2 bar (17 psi)
• Peak engine pressure 130 bar (1,900 psi)
• Air delivery Forced induction, 2x twin scroll turbochargers spinning to 186,000 rpm with electronically controlled blow-off valves
• Fuel delivery Electronically controlled direct petrol injection with spray-guided combustion, fully variable, fuel pressure 100–200 bar (1,500–2,900 psi)
• Coolant delivery 3 phase thermostat, timing chain driven water pump rated 420 litres (110 US gal; 92 imp gal) /min flow
• Oil delivery 9 litres (2.4 US gal; 2.0 imp gal) oil, dry-sump, via two-stage controlled suction pump (250 litres (66 US gal; 55 imp gal) /min), a pressure pump and a 12 litres (3.2 US gal; 2.6 imp gal) external oil tank
• Oil cooling External engine oil cooler in the front
• Charged air cooling Indirect air/water intercooling, cooling 140 °C (284 °F) charged air to 25 °C (45 °F) above outside temperature under full load
• Engine weight (dry) 209 kg (461 lb)
• Emissions standard Euro 6
• NEDC combined consumption Under 10 litres (2.6 US gal; 2.2 imp gal) /100 km (62 mi)

Applications