• Holley 550-603 HP EFI Engine Control Module and Wiring Harness Kit for LS2, LS3 and LS7
  • Holley 550-603 HP EFI Engine Control Module and Wiring Harness Kit for LS2, LS3 and LS7

Holley 550-603 HP EFI Engine Control Module and Wiring Harness Kit for LS2, LS3 and LS7

$2,849.95 USD
$2,849.95 USD
$2,849.95 USD
Shipping calculated at checkout.

Vendor : HOLLEY

Product Type : Ignitions and Electrical

Sku : HLY550-603

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ECU & Wiring Harness LS2

The Holley 550-603 HP EFI Engine Control Module and Wiring Harness Kit is designed for GM LS-series applications using LS2, LS3 or LS7 engines. The kit combines an engine control module with a wiring harness for an integrated electronic fuel injection control solution.

This system is specified for engines equipped with a 58x reluctor wheel. Its application-focused design supports LS-series engine management while providing the core components needed for electronic control and wiring integration.

Use the Holley 550-603 as a matched ECU and harness package for compatible LS2, LS3 and LS7 setups. Verify the engine configuration and 58x reluctor wheel requirement before installation to ensure the kit matches the intended application.

Features:

  • Engine Control Module: Provides electronic engine control for compatible applications.
  • Wiring Harness: Includes a wiring harness as part of the integrated kit.
  • Engine Compatibility: Designed for GM LS-series LS2, LS3 and LS7 engines.
  • Reluctor Wheel: Intended for applications using a 58x reluctor wheel.
  • Fuel Injection System: Configured for HP EFI applications.
  • Brand and Part Number: Holley 550-603.