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Holley EFI Gen V LT Engine Main Harness

Part # 558-129 Be the first to write a review

For use with Terminator X and X Max

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Holley EFI Gen V LT Engine Main Harness

Estimated Ship Date: 08/05/2026
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$611.95
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This harness is designed for use with Terminator X and X Max ECU's Only.

Features:

  • Used on Terminator X and Terminator X Max
  • Main harness
  • GM Gen V LT engines
  • Wires in protective loom

About Holley EFI

Find standalone EFI for LS, Coyote, Hemi and more at Holley.com. From engine swapping to managing up to 4000 horsepower, we have a solution for every project!

Brand Holley EFI
CategoryEngine
Crank Reluctor58x
Emission Code4
Harness ApplicationGen V LT
LT
Harness TypeMain
Part TypeEngine Control Module (ECM) Wiring Harness
Product TypeHarness
Sub CategoryWire, Cable and Related Components
UPC090127140802
Manufacturer Part Number558-129
Part Number558-129
4

This part is legal for sale or use on Racing Use Only Vehicles

The following vehicles are considered Racing Use Only Vehicles:

  • Racing Use Only Vehicles are vehicles that are used exclusively for competition that are not registered and that may never be used on the street.

WARNING: It is against the law to install this part on an Emissions Controlled Vehicle

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