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EFI System Manufacturer
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Fuel Injection Style
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EFI System Kit Number
- HLY-550-603 (1) The options in this area are not available since you have already selected choices in the area. Use the "Get Results" button for your current choices.

Holley EFI Systems Wiring Harnesses

4.77 out of 5 stars 31 Customer Reviews

Holley offers a variety of direct replacement EFI wiring harnesses, including multi-port, sequential, and throttle body injection styles. These units are made with premium components to ensure better reliability and performance for your ride--and they're compatible with many engine swaps. Holley EFI systems wiring harnesses are sold individually or as a kit; choose the model needed for your fuel injection application.

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