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Holley Performance HP EFI ECU And Harness Kit 550-603N


GM LS2 - Incl. ECU/Harness - Incl. NTK Oxygen Sensor

Pricing: $1,975.95


GM LS2 - Incl. ECU/Harness - Incl. NTK Oxygen Sensor

Holley Performance - HP EFI ECU And Harness Kit P/N 550-603N Features:

  • Simple Installation - Plug And Play
  • Significantly More Functionality Than Other Competitive ECUs
  • Laptop Programmable ECU Includes Many Base Maps For Easy Use
  • For Anything That Needs Simple And Powerful ECU/Harness Solution
  • Self Tune Fuel Strategy More Time Enjoying Your Vehicle Power
  • ECU Fully Potted/Can Mount In The Engine Compartment Or Interior
  • Sealed Automotive And Marine Grade Connectors
  • 1-5 Bar Map Sensor Capability
  • 5.7 Touchs


Holley products have been the undisputed leader in fuel systems for over 100 years. Holley carburetors power every NASCAR Sprint Cup team and every NHRA Pro–Stock champion. Holley's products include performance fuel pumps, fuel injection, intake manifolds, cylinder heads & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies, Hooker Headers, Flowtech Headers, NOS, Weiand, or Earl's, Holley products can give you the edge you need over the competition.


  • 550-603N
  • 550-603N
  • 090127687468
  • Holley Performance
  • New

Shipping Information

  • Item Requires Shipping
  • 9.0 lbs.
  • W11.0000” x H7.5000” x L12.2500”

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