Mercedes-Benz M139 engine

Mercedes-Benz M139
Overview
ManufacturerMercedes-AMG
Production2019-present
Layout
ConfigurationStraight-four engine
Displacement2.0 L (1,991 cc)
Cylinder bore83 mm (3.27 in)
Piston stroke92 mm (3.62 in)
Cylinder block materialAluminium alloy
Cylinder head materialAluminium alloy
ValvetrainDOHC
Compression ratio9.0:1
Combustion
TurbochargerOne twin-scroll, electrically assisted
Fuel systemCombined Direct and Port Fuel Injection
Fuel typeGasoline
Output
Power output285 kW (387 PS; 382 hp) base version 310 kW (421 PS; 416 hp) S-model
Torque output480 N⋅m (354 lb⋅ft) (base version) 500 N⋅m (369 lb⋅ft) (S-model)
Dimensions
Dry weight160.5 kg (354 lb)
Chronology
PredecessorMercedes-Benz M133 engine

The M139 is a turbocharged straight-four engine produced by Mercedes-Benz. It is the successor of the M133 engine. It is also the first four-cylinder engine by AMG to be specified with two outputs, assembled by hand using "one man, one engine" philosophy, and equipped with combined a port and direct fuel injection system. At 310 kW (416 hp) on its introduction, M139 was the world's most powerful four-cylinder engine in serial production with specific output of 155 kW (208 hp) per litre or 78 kW (104 hp) per cylinder.[1][2] The current top trim of the M139 produces 350 kW (469 hp), giving it a specific output of 175 kW (235 hp) per litre or 87.5 kW (117 hp) per cylinder, making it the current most powerful four-cylinder engine in serial production.

Design

The M139 engine is based on the current M260 engine, which is an upgraded version of the outgoing M270, sharing the same bore and stroke dimension as well as the block. Unlike the normal M260, the AMG engineers rotated the engine block 180 degrees so that the intake system is in the front of the engine, while the turbochargers and exhaust headers are situated between the engine and firewall.[3] The rotation optimises the engine air flow for higher performance and with shorter distance and fewer diversions. This also "allows the flattest possible and aerodynamically advantageous front section design."[4] The exhaust valves in M139 engine are bigger than ones in M133 engines for higher flow. The compression ratio is raised to 9.0:1 for M139 from 8.6:1 for M133. The two-stage fuel injection system, a first in AMG four-cylinder engine, has the piezo injectors delivering the fuel directly into the combustion chambers as first stage and solenoid valves in the manifolds as second stage for increased specific output.

An electrically assisted turbocharger system by Garrett Motion is used.[5]

Performance

The M139 engine has two specific outputs: 285 kW (387 PS; 382 hp) and 480 N⋅m (354 lb⋅ft) for the base version; and 310 kW (421 PS; 416 hp) and 500 N⋅m (369 lb⋅ft) for the S-model.

Models

Engine Power Torque Years
M139 285 kW (382 hp)
at 6,500 rpm 		480 N⋅m (354 lb⋅ft)
at 4,750-5,000 rpm 		2019-
300 kW (402 hp) 500 N⋅m (369 lb⋅ft) 2022-
310 kW (416 hp)
at 6,750 rpm 		500 N⋅m (369 lb⋅ft)
at 5,000-5,250 rpm 		2019-
M139I 350 kW (469 hp)
at 6,750 rpm 		545 N⋅m (402 lb⋅ft)
at 5,250-5,500 rpm 		2023-

M139 (285 kW version)

M139 (300 kW version)

M139 (310 kW version)

M139I (350 kW version)

References

  1. ^ Patrick George (7 June 2019). "Good Gravy: AMG Is Getting 416 Horsepower Out of Just a 2.0-Liter Turbo Four". Jalopnik.
  2. ^ Bob Sorokanich (7 June 2019). "How Mercedes-AMG Made the Most Powerful Production Four-Cylinder Ever". Road & Track.
  3. ^ "Mercedes-AMG's New 2.0 Inline-Four Develops 415bhp, Revs to 7200rpm".
  4. ^ "The world's most powerful four-cylinder engine in series production, made in Affalterbach". Mercedes-Benz USA. 6 June 2019.
  5. ^ "Nerd's Eye View: Mercedes AMG M139 Engine with E-turbo and Liquid Immersion Battery Cooling". MotoIQ. 11 April 2021.