This calibrated controller kit from Chevrolet Performance enables quicker and easier adaptation of the Chevrolet Performance LS3 LS376/525 Crate Engine for countless hot rod projects. It is specially programmed for retrofit installations, with features that make getting the vehicle running easier than if a production controller were used. The kit also includes hardware and components that does not typically come with a used or salvage yard engine, such as the wiring harness, mass airflow meter and electronic throttle pedal assembly, eliminating the need to source them separately! This controller system is a true stand-alone system for use in older vehicles, as all that's needed to get a vehicle running with it are power and ground sources, a 58-psi (400 kPa) fuel pump and an electric cooling fan.