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Holley Terminator EFI Wiring Harnesses 558-420 Fuel Injection System Harnesses, EFI, Auxiliary Input/Output Harness, EFI, Gains 4 Inputs/1 Output, Each

Holley Terminator EFI Wiring Harnesses 558-420 Fuel Injection System Harnesses, EFI, Auxiliary Input/Output Harness, EFI, Gains 4 Inputs/1 Output, Each

A$132.75
IN STOCK! Est Ship 4-7 days. This item is IN STOCK at one of our warehouses or distribution centres, the ETA is the approximate time required to prepare your order for dispatch.
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Description

Holley Terminator EFI wiring harnesses are replacement throttle body wiring harnesses and engine control wiring harnesses for specific Electronic Fuel Injection kits. These relays allow you to perform functions and features that are programmed with your Holley EFI laptop software. The software also contains instructions on how to program them. Holley wiring accessories give you the expertise needed to get the job done right.

Part Type

Wire Harness Kit - EFI Terminator I/O

Data: v4.2 - Upd: 2026-10-13 18:48:29

Specifications

Product Attributes - Brand
Holley
Product Attributes - Manufacturer's Part Number
558-420
Product Attributes - Part Type
Fuel Injection System Wiring Harnesses
Product Attributes - Product Line
Holley Terminator EFI Wiring Harnesses
Product Attributes - UPC
090127688519
Product Attributes - Quantity
Sold individually.
Product Attributes - Notes
Harness contains four extra input wires and one extra output wire that the base Terminator EFI harness does not contain.

Reference Information

Brand Name/s Holley
StreetFX SKU hly558-420
SFX Item ID 4782203
Supplier Item Code 4782203
Manufacturer SKU 558-420
Manufacturer UPC 90127688519
Alternative References HOL558-420, Inputs/1

Compatibility

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