Tinman wrote:
I've heard that the Duramax ECM uses part numbers from different injectors for differential fueling of individual injectors in the same motor. Instead of using good quality control and flow matching each injector, Bosch just makes the injector tips (by EDM I think) and then flow test them.
We build diesel fuel injectors where I work. It's not done this way because of lack of quality control. It's done because of the extreme difficulty of holding a tolerance while EDMing multiple 150 micron diameter holes. Injectors would be even more expensive if you tried to make them all flow the same within some arbitrarily tight tolerance. Just let the ECU compensate for the difference. It's cheaply done in software.