S&S Modified 12mm CP3 Injection Pump is recommended for applications up to 1,000HP on Common Rail 5.9L & 6.7L Cummins applications. For best performance use a 150 GPH or higher lift pump. This modified CP3 offers fueling capabilities up to 4,500 RPM, where a stock CP3 falls off at 3,000 RPM. Based off of a 6.7L Pump. Custom tuning is required. No Core Fee.