Performance Parts

The CAN to USB communication cable provides the user with real tuning time access to the ECU. This cable can be used with Holley EFI, Sniper EFI, and Terminator X Tuning Software. Which can be downloaded for free from the Support section of our website!

Gen III HEMI Harness with TPS and Idle Air Control Connections. This wiring harness interfaces a Holley EFI ECU to a Gen III HEMI engine with an aftermarket cable actuated throttle body. It is meant to be used in conjunction with an injector harness, a...

Are you tired of scouring the junkyard for stock ls coil sub harnesses? Introducing the new Holley EFI LS Coil Sub Harness. This coil sub harness is intended to be used with factory LS coils and various Holley EFI main harnesses with Coil-on-plug...

I/O Adapter w/Terminated Vehicle Harness

PN 558-420 contains 5 extra input/output wires that the base Terminator EFI harness does not contain. It contains Input wires for Inputs 1-4. It contains one wire for Output 2. These inputs and outputs can perform features and functions that must be...

MULTEC 2 INJECTOR HARNESS - EARLY TRUCK

Expanding on our Transmission Control options from Holley EFI. This new harness 558-455 from Holley EFI provides plug and play transmission control for the 2009+ GM 4L60 when used with a Dominator ECU. The 2009+ GM 4L60E contains an internal turbine...

Introducing Coyote Twin Independent Variable Cam Timing Control from Holley EFI! Do you have a coyote crate engine going in your dream car? Is your weekend road race warrior powered by a coyote junkyard engine with locked cams? Unlock the full potential...

Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley...

Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley...

Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley...