The Mercedes Benz Om606 engine has garnered a reputation as a robust and highly tunable diesel powerhouse, especially within the performance and modification communities. While discussions around this engine might seem to have surfaced some years ago, its popularity and potential are more relevant than ever, particularly in the US where interest in high-performance diesel conversions is rapidly growing. For enthusiasts and mechanics alike, the OM606 represents an exceptional platform for creating powerful and reliable builds.
The OM606: A Mechanical Marvel Ready for High Performance
The OM606 stands out, especially when compared to its OM603 predecessors and even contemporary engines, due to its inherent strength and ease of modification. While early OM603 engines had some well-documented issues, these are largely irrelevant now as those engines have either been phased out or resolved through maintenance over time. The OM603, and particularly the OM606, are celebrated for their durability and mechanical nature, making them ideal for swaps into cars, trucks, and off-road vehicles where reliability and straightforward maintenance are paramount. These engines are fundamentally mechanical, simplifying repairs and upgrades without the complexities of extensive electronic controls in their base form.
For those looking to significantly boost power, the OM606 shines. Remarkably, it can reliably handle 400-500 wheel horsepower (WHP) with relatively straightforward modifications, without needing to delve into internal engine work. This level of power is achievable with key upgrades focusing on the fuel and air delivery systems. The core modifications typically involve:
- Injection Pump Upgrade: Upgrading to a performance-oriented injection pump is crucial. A 7.5mm pump is often sufficient for street performance, while an 8mm pump is recommended for those targeting serious power figures exceeding 600 horsepower. Dieselmeken pumps are often cited as a high-quality option.
- Turbocharger and Exhaust Header: A larger turbocharger and a custom exhaust header are essential for increasing airflow and reducing backpressure, both critical for higher horsepower output.
- Intercooler: An upgraded intercooler is necessary to manage the increased intake air temperatures from a larger turbo, ensuring denser air for combustion and preventing performance-robbing heat soak.
For enthusiasts seeking even greater control and tunability, moving towards electronic injection with an “E Injection pump” and a DSL1 computer opens up a wider range of adjustments. This setup allows for precise tuning of fuel delivery, boost pressures, and rev limits. Combined with a transmission controller like OFGear for electronic transmissions, the level of customization becomes extensive, allowing fine-tuning of shift firmness and points, even incorporating paddle shifters.
Transmission and Drivetrain Considerations
The OM606’s versatility extends to transmission compatibility. It can be paired with a range of transmissions, both manual and automatic. Adapting to older chassis is simplified by the availability of adapter rings for OM60X engines, facilitating swaps into various vehicles. The stock Mercedes 722.3 4-speed automatic transmission is known to handle considerable power in its standard form, while the 5-speed 722.6 transmission is another robust option, particularly when built to AMG V8 specifications or sourced directly from AMG models. For manual conversions, certain BMW manual transmissions are known to be relatively straightforward to adapt.
Pushing the Limits: Extreme OM606 Performance
For those aiming for the absolute pinnacle of OM606 performance, surpassing the 600 horsepower mark and venturing into high RPM ranges (6000-8000 RPM), further internal upgrades become relevant. These include beefier connecting rods, main bearing cradles, and valve spring kits. Even with these enhancements for extreme power, the OM606 remains remarkably efficient, potentially achieving around 30 MPG even in high-performance configurations – a stark contrast to gasoline engines producing comparable power.
Companies like DieselpumpUK, FTune, and Turbobandit are at the forefront of developing performance parts and tuning solutions for the OM606, showcasing the engine’s capabilities in diverse applications ranging from Mercedes G-Wagens and classic sedans to American trucks like the Ford F-250. BenzForce in the US is also contributing by importing European performance parts, further expanding the accessibility of OM606 upgrades.
The Broader OM60X Family and Future Developments
While the OM606 takes center stage, it’s part of a broader OM60X engine family that includes the OM602, OM603, and OM605. These engines share similar robust characteristics and modification potential, making them viable options for various projects. Looking ahead, even newer common rail diesel engines from Mercedes, succeeding the OM606, are being explored for their performance tuning potential, with experts like Baldur Gislason (DSL1 creator) and teams like Black Smoke Racing pushing the boundaries of diesel performance.
Conclusion: The Enduring Appeal of the OM606
The Mercedes Benz OM606 engine stands as a testament to robust diesel engineering, offering an exceptional blend of reliability, tunability, and surprising fuel efficiency even when heavily modified for high performance. Its mechanical foundation appeals to those who value simplicity and durability, while its power potential excites enthusiasts looking for a unique and potent alternative to gasoline engines. Whether for a classic car swap, an off-road build, or a high-performance street machine, the OM606 continues to be a superstar engine deserving of its dedicated following.
