Affalterbach is synonymous with high performance, and at the heart of its latest compact models lies a revolutionary powerplant: the Mercedes-AMG 2.0-liter M 139 engine. This isn’t just any four-cylinder engine; it’s the world’s most powerful turbocharged four-cylinder in series production, delivering up to an astonishing 416 hp. For enthusiasts and experts alike, the “4 Cyl Mercedes” designation now carries a new weight, representing a pinnacle of engineering and performance from Mercedes-AMG.
The M 139 engine marks a significant leap forward, even surpassing AMG’s previous four-cylinder champion, the M 133, by a remarkable 40 hp. Torque also sees a substantial increase, climbing from 350 to a potent 369 lb-ft. When considering power per liter, this 4 cyl mercedes engine achieves an incredible 208 hp, outperforming many engines found in well-known supercars. This powerhouse is meticulously crafted in Affalterbach, adhering to the revered “One Man, One Engine” principle on a cutting-edge production line.
This exceptional 4 cyl mercedes engine is offered in two output stages for Mercedes-AMG’s compact car range, catering to different performance appetites: a formidable 416 hp for the S-model and a still impressive 382 hp in the base version. This tiered approach, mirroring the successful strategy used with V8 AMG Performance models, ensures that customer desires for varying levels of intensity are met.
Beyond the sheer numbers, the M 139 engine distinguishes itself with its lightning-fast responsiveness. AMG engineers have meticulously sculpted the torque curve with “torque shaping” to achieve this. The peak torque of 369 lb-ft (354 lb-ft for the base variant) is sustained across a broad rev range of 5000-5250 rpm (4750-5000 rpm for the base version).
This deliberate tuning lends the 4 cyl mercedes engine a power delivery reminiscent of a naturally aspirated engine, amplifying the emotional connection for the driver. Furthermore, the engine developers have engineered a torque curve that builds dynamically from lower engine speeds, enhancing agility and responsiveness. The surge of torque at higher rpm encourages enthusiastic revving, and the engine’s high maximum engine speed of 7200 rpm solidifies the M 139’s identity as a true sports engine within the “4 cyl mercedes” family.
Tobias Moers, Chairman of Mercedes-AMG GmbH at the time of release, aptly stated, “We already set the benchmark in the segment with the preceding engine. This fundamentally new four-cylinder presented us with the challenge of doing even better. And we succeeded with a number of sometimes revolutionary solutions. With the M 139, we have once again impressively demonstrated the engine expertise of Mercedes-AMG. Not only is the output per liter unrivalled for a turbocharged engine, the high level of efficiency also demonstrates that the internal combustion engine still has further potential.” His words underscore the significance of this 4 cyl mercedes engine as a testament to AMG’s engineering prowess.
Reinventing “One Man, One Engine” for the Modern Era
The M 139 4 cyl mercedes engine is a product of pure hand assembly. Mercedes-AMG has reimagined the “One Man, One Engine” philosophy for the M 139, integrating Industry 4.0 methodologies into a newly designed production line within the Affalterbach engine factory. This innovative approach prioritizes ergonomics, material handling, quality control, sustainability, and efficiency. AMG’s vision of “smart production” translates to maximum flexibility, transparency, and exceptional efficiency, ensuring and elevating engine quality and production processes through cutting-edge digital technologies.
Emmerich Schiller, COO and member of the Board of Management at Mercedes-AMG GmbH, explained the evolved process: “We have completely revised the principle of “One Man, One Engine” for assembly of the M 139. The result is an ultra-modern production process that places the focus on people. To achieve this, we created the ideal working conditions in a bright, precisely organized and clean environment for our employees. This provides the best basis for continuing to ensure our high quality level even as the technology becomes more complex.” This human-centric approach, combined with advanced technology, is what defines the production of every “4 cyl mercedes” M 139 engine.
The 180-Degree Rotation Advantage in this 4 Cyl Mercedes
The M 139 4 cyl mercedes engine incorporates numerous intelligent design elements. Unlike the transversely mounted four-cylinder M 260 in the “35” models or the preceding M 133 engine, the new Mercedes-AMG M 139 is rotated 180 degrees around its vertical axis. This strategic rotation positions the turbocharger and exhaust manifold at the rear, towards the firewall, while the intake system is now located at the front.
This configuration enables a flatter and more aerodynamically optimized front-end design for vehicles housing this 4 cyl mercedes engine. Furthermore, the new arrangement optimizes airflow with shorter, less convoluted paths for both intake and exhaust, enhancing engine breathing and overall efficiency.
Roller Bearings: Enhancing Turbocharger Response in the 4 Cyl Mercedes
The twin-scroll turbocharger in this 4 cyl mercedes engine is engineered for both rapid response at lower engine speeds and substantial power at higher rpm. The turbine housing is divided into two parallel flow passages, working in concert with divided ducts in the exhaust manifold to direct exhaust flow to the turbine in a separated manner.
This sophisticated design minimizes negative interference between cylinders during load cycles and optimizes the gas cycle. The outcome is improved torque delivery at lower engine speeds and exceptionally quick turbocharger response, crucial for the dynamic performance expected from a “4 cyl mercedes” AMG.
Furthermore, a notable innovation is the use of roller bearings for the compressor and turbine shafts – a feature shared with the top-tier AMG 4.0-liter V8 engine in the AMG GT 4-door Coupe. These roller bearings minimize mechanical friction within the turbocharger, allowing it to respond more eagerly and reach its maximum speed of up to 169,000 rpm with greater rapidity. This advanced turbocharger technology is a key contributor to the impressive performance of this 4 cyl mercedes engine.
Electronic Charge Pressure Control: Precision and Responsiveness
With a peak charge pressure of 2.1 bar (1.9 bar in the base version), the 2.0-liter turbo engine in this 4 cyl mercedes application demonstrates its high-performance credentials. The electronically controlled wastegate (exhaust relief valve) provides even finer and more flexible charge pressure regulation, optimizing responsiveness, especially during acceleration from partial load. The system intelligently considers numerous parameters for precise control.
Key inputs for the wastegate control unit include charge pressure, throttle flap position, and knock tendency. Modifying signals encompass intake air temperature, engine temperature, engine speed, and atmospheric pressure. This intelligent management even allows for temporary charge pressure boosting (overboost) during acceleration, further enhancing the dynamic capabilities of this 4 cyl mercedes powerplant.
Cooling the turbocharger is achieved through a combination of fresh air, oil, and water. Fresh air is specifically channeled from the radiator grille to the charger via the engine cover, designed as an air deflector, and ducts beneath the hood. This cooling strategy draws upon principles and experience gained from cooling internally mounted turbochargers in AMG 4.0-liter V8 engines, starting with the AMG GT in 2014. Integral insulation within the turbine housing further contributes to thermal management.
The Robust Crankcase of the 4 Cyl Mercedes Engine
The crankcase of this 4 cyl mercedes engine is constructed from chill-cast aluminum, chosen for its exceptional material properties. In this process, molten aluminum is poured into a metallic mold. The mold’s excellent thermal conductivity, aided by water cooling, allows for rapid cooling and solidification of the molten metal. This results in a fine-grained, dense structure that ensures very high strength. Complex internal geometries are made possible through the use of enclosed sand cores.
The closed-deck construction, a design principle borrowed from motor racing, delivers outstanding rigidity with minimal weight and can withstand peak combustion pressures up to 160 bar. The areas surrounding the cylinders are largely solid, with only small ducts for coolant and engine oil penetrating the cover plate. The crank assembly, featuring a lightweight, forged steel crankshaft and forged aluminum pistons with optimized piston rings, balances low friction with high strength. The engine’s maximum speed is 7200 rpm, with peak power achieved at 6750 rpm. The sump incorporates baffle plates to ensure consistent engine oil supply to all critical components, even under high lateral acceleration forces, a crucial detail for a high-performance 4 cyl mercedes.
NANOSLIDE Cylinder Liners: Minimizing Friction for Maximum Performance
To minimize friction between pistons and cylinders, the cylinder liners in this 4 cyl mercedes engine are treated with patented NANOSLIDE technology. This coating creates a mirror-like surface on the linings, reducing friction to a minimum. NANOSLIDE is twice as hard as conventional grey cast-iron liners, significantly enhancing durability.
Developed by Daimler AG, NANOSLIDE is protected by over 90 patent families and more than 40 patents. It was first implemented in AMG’s M 156 engine and has been utilized in numerous AMG engines since, including the Formula 1 engine of Mercedes-AMG Petronas Motorsport. Its inclusion in this 4 cyl mercedes engine highlights AMG’s commitment to cutting-edge technology and performance.
Enhanced Gas Cycles with Larger Exhaust Valves
Relocating and slightly angling the injection nozzles and spark plug system within the cylinder head of this 4 cyl mercedes engine allowed for the enlargement of the exhaust valves compared to the previous M 133 engine. These larger exhaust cross-sections facilitate the low-loss expulsion of gases from the combustion chambers and reduce overall piston venting action.
More efficient cylinder head cooling is achieved through seating rings with a reduced installed height and a cooling borehole positioned near the combustion chamber, in the web area between the exhaust seating rings. Cooling performance is further enhanced by a near-surface water jacket geometry, a faster flow rate, and optimized volumetric flow rate. A multi-layered, state-of-the-art corrugated metal seal isolates the cylinder head from the crankcase, ensuring robust sealing under high pressures and temperatures within this 4 cyl mercedes engine.
Two overhead camshafts control the 16 valves via weight-optimized roller cam followers. Camshaft adjustment on both the inlet and outlet sides enables excellent response and optimizes the gas cycle for every operating point. Variable CAMTRONIC valve control on the exhaust side, featuring two cams per valve with differing geometries, provides further refinement. Depending on the cam setting, exhaust valves can be opened for short or long durations, optimizing responsiveness at low engine speeds, fuel efficiency at medium rpm, and full power delivery at high rpm, showcasing the versatility of this 4 cyl mercedes engine.
Dual-Stage Fuel Injection: Best of Both Worlds
Turbocharging and spray-guided direct injection in this 4 cyl mercedes engine not only yield high power output but also improve thermodynamic efficiency, reducing both fuel consumption and exhaust emissions. For the first time in an AMG high-performance four-cylinder, a two-stage fuel injection system is employed.
In the first stage, rapid and precise piezo injectors deliver fuel to the combustion chambers at pressures up to 200 bar. This process can be multi-stage and is managed by the engine management system as needed. The second stage incorporates additional intake manifold injection using solenoid valves, necessary to achieve the engine’s high specific output. The electronically controlled fuel supply operates at a pressure of 6.7 bar, ensuring consistent and optimized fuel delivery for this high-performing 4 cyl mercedes.
Sophisticated Cooling System: Maintaining Peak Performance
The high output of this 4 cyl mercedes engine demands an intelligently designed cooling system. An auxiliary radiator in the wheel arch complements the primary unit in the front module. A low-temperature circuit is also utilized for air/water intercooling. A high-performance electric pump, working in conjunction with the series-connected intercooler, assists coolant flow through the radiators. This ensures optimal cooling of the highly compressed charge air, contributing to peak engine performance.
Transmission oil cooling is integrated into the engine’s coolant circuit and is further aided by a heat exchanger mounted directly on the transmission. The engine control unit is positioned on the air filter housing, where it benefits from airflow cooling. This comprehensive cooling system is vital for maintaining the performance and reliability of this powerful 4 cyl mercedes engine.
Electric Water Pump: Efficiency and Control
The demand-controlled electric high-performance water pump in this 4 cyl mercedes engine operates independently of engine speed. Delayed activation during warm-up allows the engine block to heat up more quickly, positively impacting friction, fuel consumption, and emissions. The pump can be switched on or off as needed during periods of lower power demand or at low engine speeds.
Furthermore, the electric water pump ensures full engine output and optimal heat dissipation across the entire engine speed range. It also provides protection against thermal damage when idling in very high ambient temperatures. Features such as alternator management, ECO start/stop with rapid restarting, gliding function, and a gasoline particulate filter are also integrated into the technology package of this advanced 4 cyl mercedes engine.
A New Assembly Process: Enhancing Efficiency and Ergonomics
The new AMG 2.0-liter turbocharged four-cylinder engine, internally designated M 139, is assembled entirely by hand, upholding the traditional AMG “One Man, One Engine” principle. However, this process is now enhanced with a completely new, digitally supported and logistically optimized approach.
People are central to this evolved process, with employees supported by digital tools. The focus is on leveraging intelligent, flexible technology. A combination of highly flexible line assembly and preconfigured shopping carts using driverless transport systems forms the core of this modern production methodology. Sustainability was also a key consideration in the planning of the new M 139 production line, with renewable energy sources used in production and significant reductions in CO2 emissions, water consumption, and waste. This reflects AMG’s commitment to both performance and responsible manufacturing for its 4 cyl mercedes engines.
Ergonomic Assembly Carts: Streamlining the Workflow
The assembly cart used for building the M 139 4 cyl mercedes engine was co-developed with the assembly team. It features its own independent power supply, eliminating the need for power cables. All essential operating fluids and tools are arranged ergonomically on and around the cart, simplifying work, minimizing movement, and boosting efficiency. An integrated tablet PC provides employees with precise, clear work instructions, making paper manuals obsolete and creating a paperless manufacturing environment.
The “Blue Sky” Workplace: A Modern Assembly Environment
New cordless screwdrivers are readily accessible and no longer require retrieval from overhead suspended, wired tools. This improvement led employees to dub their workspace “blue sky” due to the absence of power cables hanging from the ceiling. The assembly shop presents a bright and airy atmosphere, fostering a pleasant working climate. Extensive digitization enhances both manufacturing efficiency and flexibility. Each tool is connected to the engine assembly shop’s WLAN, enabling automated enabling and torque settings for each assembly stage via indoor tracking. Furthermore, all completed tasks are digitally recorded, ensuring optimal quality assurance, traceability, and transparency in the production of every 4 cyl mercedes M 139 engine.
Driverless Transport Systems: Just-in-Sequence Logistics
Each assembly technician is accompanied by a driverless transport system. Its shopping cart contains precisely the components needed for the engine being assembled, ensuring efficient and error-free parts delivery for each 4 cyl mercedes unit.
The transport systems are loaded at the Mercedes-AMG logistical center in Marbach and delivered to the production line on a “just in sequence” basis. Indoor tracking via WLAN enables autonomous control. All components are digitally tracked throughout the process. The assembly and transport carts are styled in a black-and-white Mercedes-AMG design, featuring slogans like “START YOUR ENGINE” or “AMG PERFORMANCE INSIDE,” fostering motivation and company identification. The shop floor design incorporates hatching and white-and-red stripes, reminiscent of racetrack curbs and guide rails, further enhancing the AMG atmosphere in the production of these high-performance 4 cyl mercedes engines.
Efficient Test Stations: Enhanced Quality Assurance
Assembly efficiency is further improved by reducing the number of test stations. This is achieved by consolidating several individual stations into three central stations: drag torque test, leakage test for oil/coolant and fuel systems, and complete engine water jacket test. This consolidation results in significant time savings and greater efficiency. All parameters and measured values are digitally recorded and stored, allowing for the tracking of each individual engine’s assembly process. This rigorous testing regime ensures the high quality and performance expected from every 4 cyl mercedes AMG engine.
The “One Man, One Engine” assembly philosophy remains a hallmark of the Mercedes-AMG brand. Another distinguishing feature of the M 139 is the AMG engine plate, bearing the signature of the assembly technician. All assembly technicians for the new four-cylinder engine underwent extensive further training specifically for the M 139, highlighting the specialized expertise involved in crafting each 4 cyl mercedes engine.
Technical Data at a Glance
| Mercedes-AMG M 139 2.0 liter turbocharged four-cylinder engine | |
|---|---|
| Displacement | 1991 cc |
| Bore x stroke | 83.0 x 92.0 mm |
| Output | 416 hp at 6750 rpm (S-model) 382 hp at 6500 rpm (base version) |
| Peak torque | 369 lb-ft at 5000-5250 rpm (S-model) 354 lb-ft at 4750-5000 rpm (base version) |
| Max. engine speed | 7200 rpm |
| Compression ratio | 9.0:1 |
| Turbocharging | One twinscroll turbocharger with roller-bearing compressor and turbine wheels |
| Max. charge pressure | 2.1 bar (S-model) 1.9 bar (base version) |
| Mixture formation | Combined direct and manifold injection. 1.) Third-generation multiple direct injection. Fast and precise piezo injectors spray the fuel into the combustion chambers at high pressure 2.) Additional intake manifold injection with solenoid valves |
| Cylinder head | Two overhead camshafts, 16 valves, adjustable intake and exhaust camshafts, CAMTRONIC valve timing adjustment for the exhaust camshaft |
| Max. air mass throughput | 2,645 lb/h (S-model) 2,425 lb/h (base version) |
| Engine weight (wet) | 353.8 lbs |
