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Holley Universal V8 MPFI EFI Harness Kit 558-504

Item #22893

Holley Universal V8 MPFI EFI Harness Kit 558-504
Universal V8 MPFI
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Quantity: close

In stock


• This item ships directly from the manufacturer

• Expected delivery time is 1 – 2 weeks

• Not available in Eastwood Retail Stores

• Order may not be changed or canceled

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An EFI system depends heavily on being supplied a clean and constant voltage source. The grounds of an electrical system are just as important as the power side. Our Holley EFI Harness Kit comes complete with the main harness, power harness and injector harness to support your primary system!


  • Harness Kit Includes; Main Power Harness, Universal MPFI Main Harness, v-8 Injector Harness
  • Simple installation
  • Works with HP or Dominator ECU's

More info...


(1) Holley Universal V8 MPFI EFI Harness Kit 558-504


Brand: Holley EFI
Emission Code: 4
Harness Application: Ford, GM, Universal
Ignition Type: CD Ignition (No Timing Control)
Injector Connector: Jetronic / Minitimer (Bosch)
Product Type: Harness Kit
Part Number: 558-504

This part is legal for sale or use on Racing Use Only Vehicles

The following vehicles are considered Racing Use Only Vehicles:

• Racing Use Only Vehicles are vehicles that are used exclusively for competition and that are not registered and that may never be used on the street

WARNING: It is against the law to install this part on an Emissions Controlled Vehicle


Instructions for Part# 558-504

***NOTICE: You will need to purchase an ECU and O2 Sensor to make this a complete kit.


1 Year Manufacturers Warranty

Eastwood Offers Free Lifetime Technical Support

Click here for product SDS information

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