BMW CP4.1 Pump Modified “Stroker” Shaft (OEM-Based)
The modified CP4.1 pump shaft (“stroker shaft”) is manufactured using an OEM core and designed to significantly increase the performance of the CP4 pump.
When installed, the pump can supply enough fuel for systems requiring up to 450 hp.
Compatible with BMW diesel engines N47 and B47 equipped with a CP4.1 pump.
A stroker-type shaft increases the pump’s stroke length, allowing it to deliver more fuel per revolution while maintaining the factory pump design and control logic. This prevents fuel starvation under high load and ensures stable engine operation in higher-power applications.
Compatibility
Fits BMW diesel engines N47 and B47 with the CP4.1 pump
Intended for engines where the stock pump cannot meet fuel demand
Fits only CP4 pumps with a smooth housing (as shown on the right side of the reference image)
Not compatible with pumps that have housing protrusions (as shown on the left side)
Installation
Recommended to be installed by professionals experienced with high-pressure fuel systems
Can be installed by an advanced DIY user with proper tools and the ability to work in extremely clean conditions
(any contamination may damage the pump or shorten its lifespan)
Recommendation
The modified shaft increases pump output but does not protect against inherent CP4 pump failure modes.
Therefore, we strongly recommend installing a CP4 Fuel System Protection Kit (Disaster Prevention Kit) to protect the rail and injectors in case the pump fails.
Included in the package
Modified CP4.1 pump shaft (pump not included)
Installation manual
