
558-131 Variable Valve Timing (VVT) Harness for Gen III Hemi w/Terminator X or X Max EFI
Holley 558-131 Variable Valve Timing (VVT) Harness:
- Connects to the factory Gen III HEMI VVT sub-harness
- Compatible with any Holley EFI Gen III Hemi Main Harness connecting to the power tap, input, and output connectors
- Allows control and tuning of the VVT solenoid to adjust the power band of the engine
Holley 558-131 Variable Valve Timing (VVT) Harness Note:
- Requires Terminator X Firmware and Software V2 Build 50 (Terminator X V2.0.50 Software)
Harnesses to Install a GEN III Hemi in Your Hot Rod
Take control of your Gen III Hemi with Holley Wiring Harnesses capable of controlling fuel, spark, transmission, and more.
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Simplify your Gen III HEMI swap with confidence using Holley Gen III Hemi Wiring Harnesses—precision-engineered to deliver maximum performance with minimum hassle. Whether you're working with a late-model 5.7L, 6.1L, or 6.4L HEMI engine, these plug-and-play solutions make integrating modern powerplants into your project car easier than ever.
Designed for seamless compatibility with Holley EFI systems, these wiring harnesses offer clean routing, factory-style connectors, and labeled wires for effortless installation. If you're tired of splicing factory looms or chasing down wiring diagrams, Holley’s harnesses eliminate the guesswork—helping you get your build on the road faster and more reliably.
Each HEMI stand alone harness is tailored to work with specific Gen III configurations, ensuring accurate sensor readings, proper ignition timing, and optimal fuel delivery. The result? Better drivability, improved tuning capability, and a professional-level finish that’s ready for the track or the street.
Whether you're upgrading a classic Mopar or customizing a restomod, a 5.7 HEMI stand alone harness from Holley delivers the performance foundation your project demands. Built with durability and flexibility in mind, this harness stands up to the demands of high-horsepower builds while maintaining a clean OEM look.
Take the hassle out of modern engine swaps. Choose Holley for reliable wiring solutions that save you time and keep your project moving forward. Order your Holley Gen III Hemi stand alone harness from JEGS today and bring your HEMI-powered vision to life.




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