Holley EFI LS main harnesses have a MAP sensor connecter designed for use with a LS1/2 style MAP sensor. The 558????416 is an Adapter harness that allows for Holley LS2 Harness PN 558????103 to be...
This sensor is designed to trigger from a ferrous metal (magnetic steel) target, such as Holley's 60????2 crank trigger wheels. It can also be used for a cam sensor trigger and other applications.