Upgrading the turbocharger on Mercedes Om647 and OM612 engines can significantly improve performance. This article explores a Holset turbo kit designed for these engines, focusing on fitment, turbo selection, and control strategies. The project aims to provide a robust and cost-effective solution for enhanced power output.
Exploring Holset Turbo Options for Mercedes Diesels
Initial fitment tests utilized an Hx35w turbocharger. Potential turbo options include the Hx30w, Hx35w, and Hx40w for T3 flanged applications. For T25 flanges, the He200wg and He221w are being considered. A custom flange is under development to adapt Holset Variable Geometry Turbocharger (VGT) units.
Turbo Control Strategies for OM647
The OM612 engine utilizes vacuum-controlled turbo actuation, while the OM647 employs an electronic actuator. The project aims to disable the electronic turbo control on the OM647, similar to a modification performed on an Audi. This allows the use of simpler and less expensive stock wastegate actuators. While this approach sacrifices the variable nozzle turbine (VNT) benefits of the original GT2256 turbo, it significantly simplifies the system and reduces costs.
Current efforts involve tuning the OM647 ECU to manage fuel delivery and accommodate the deactivated turbo control. Accessing the OM612 ECU presents a challenge, and solutions for this engine are still under consideration.
Future Developments: Compound Turbocharging for the OM647
Looking ahead, a compound turbocharger system is planned to further enhance performance and approach the efficiency of a VNT setup. This involves combining two turbochargers in series to broaden the effective operating range and minimize turbo lag.
This project addresses the lack of readily available performance upgrades for these robust Mercedes diesel engines. Successfully bypassing the immobilizer on the OM647 could potentially open up opportunities for engine swaps into other platforms.
