This is the factory LT4 high pressure fuel pump (HPFP). Cross references to 12688607, 12694529.
Part Number: 12711668
Description:
Mechanical fuel pump flow has been one of the primary limiting factors for the aftermarket when trying to increase the power output of the GM direct injection V8 engines. The OEM LT4 HPFP is the highest flowing factory HPFP pump option available for the Gev V LT applications and is a common upgrade for LT1, L83 and L86 applications seeking to push the limit. This pump provides approximately 20% more flow than the standard LT1 HPFP and up to 30% more flow than the L83 HPFP.
Some aftermarket higher lift fuel pump camshaft lobe designs may require a lash cap to compensate for the smaller camshaft base circle
Some aftermarket higher lift fuel pump camshaft lobe designs may require a higher load spring on the pump to maintain fuel pump lifter control.
