HPCR Injector Changes throughout the years
Some have asked about changes throughout the years.
1. With the model year 2003-2004 injectors there were problems with the high pressure sealing ring. Bosch solved that problem by changing its design.
2. Another problem was wear on the nozzle needle guidance and tip. Bosch introduced a wear coating on the needle. Bosch improved the particle robustness with that coating on the needle and with a coating on the valve seat.
3. There was a design change in the contact area from the valve piston to the nozzle needle. They eliminated the bigger intermediate pin and changed it to the smaller pin / puck design. That reduced side forces on the nozzle needle which also reduced the wear on the guidance and made the injector more stable at low rail pressures when the forces for opening and closing are low.
There have been no body changes beside the outer coating.
The 6.7l Cummins injector is a different injector generation, so its internals are different. Since 2007 when it came to the Cummins, there have been only very small optimizations. No big changes.
Hope this is a help!
Thank you!