Expand Your Dominator EFI Capabilities with the J3 Harness

The Holley EFI 558-403 J3 auxiliary input/output harness is designed to provide maximum flexibility for your Dominator EFI system. If you are looking to integrate additional sensors, switches, or control outputs, this harness is the professional solution. It allows you to tap into the advanced features of the Dominator ECU, enabling custom configurations that go far beyond basic engine management.

Why Integrate the J3 Harness?

• Dedicated I/O Access: Provides direct access to the J3 port, allowing for expanded sensor and control functionality.
• Factory-Spec Quality: Built with high-temperature wiring and sealed connectors to ensure reliable operation in demanding environments.
• Versatile Application: Perfect for adding cooling fans, fuel pump triggers, or specialized data logging inputs.
• Clean Installation: Eliminates the need for messy splicing, providing a factory-look finish to your custom wiring project.

Whether you are setting up a complex race car or a highly modified street vehicle, the 558-403 harness ensures that your auxiliary components communicate perfectly with your ECU. By keeping your wiring organized and secure, you reduce the risk of electrical faults and improve the overall reliability of your EFI setup. Trust GGCRACING to provide the professional-grade components you need to take your engine management to the next level.