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558-129 Main Wiring Harness for GM Gen V LT Engines w/Terminator X or X Max ECU
InfoVehicle Info Needed
HOLLEYPART NUMBER: 510-558-129

558-129 Main Wiring Harness for GM Gen V LT Engines w/Terminator X or X Max ECU

$61195
ShippingShips on Sep 14, 2026
Lowest PriceLowest Price Guarantee

Main Harnesses
    Main Wiring Harness
  • For GM Gen V LT Engines
  • Fits Terminator X or X Max ECU
  • Sold Individually

    This Holley 558-129 Main Wiring Harness is for use with GM Gen V LT engines with a 58x crank reluctor and using a Holley Terminator X or X Max ECU only.

    Emissions Note:

    This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

    CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART

    Wire Harnesses to Complete Your LT Engine Swap

    Holley GM Gen V LT Engine Wiring Harnesses are the solution for a clean, trouble-free LT engine swap project.

Part TypeWiring Harness
Product LineHolley GM Gen V LT Engine Wiring Harnesses
BrandHOLLEY
Package Height4.45
Package Width14.7
Package Length15.15
Weight5.6 PG
QuantitySold individually
Injection StyleDirect
Engine Management System Component TypeMain Engine Harness
Vendor Part Number558-129
Package Qty1
Package TypeEA
No Questions
No Reviews
Please click here to download the instructions PDF file

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Some parts are not legal for use in California or other states with similar laws / regulations
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