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Holley EFI Unterminated Main Harnesses 558-126 Wiring Harnesses, EFI, Harness, Unterminated, Flying Lead, 15 ft. Long, J1A/J1B Connectors, Plug Seals Included, Universal, Each

SKU: HLY558-126

Wiring Harnesses

Holley EFI Unterminated Main Harnesses 558-126 Wiring Harnesses, EFI, Harness, Unterminated, Flying Lead, 15 ft. Long, J1A/J1B Connectors, Plug Seals Included, Universal, Each

SKU: HLY558-126

Wiring Harnesses
A$945.52
IN STOCK! Est Ship 4-7 days. In stock at 2 locations (more than 10 available)

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Description

Engine Wiring Harness - Flying Lead - 15 ft Long - Crimped - Universal - Kit


Data: v2 - Desc: v4.2 - Upd: 2026-11-08 02:14:56

Data: v4.2 - Upd: 2026-11-08 06:35:09

Features

Vehicle Compatibility and Return Conditions.

This item was designed and engineered in the USA for US domestic vehicles. OBD tools, ECUs, dongles, programmers, and tuners may have limited compatibility with vehicles outside the USA due to regional differences in emission standards and system configurations. Some features and functionality may vary depending on the vehicle and location.

Some electronic tuning devices and programmers require activation, registration, or pairing with a specific vehicle’s VIN (Vehicle Identification Number). Once activated or paired, these devices may become permanently associated with that vehicle, restricting or preventing their use on another vehicle, resticting our ability to offer returns or exchanges.

Please review the product details and images to ensure it meets your needs. For clarification or assistance, feel free to contact a StreetFX agent. Note: Returns are not accepted for special order or tuning products unless the unit is deemed faulty.

(keyword: efi)

Images are supplied by the manufacturer and may be generic. While all efforts are made to provide accurate pictures, there may be differences in the actual product, such as colour, quantity, version, or included components. Please carefully review the description and specifications for details on inclusions or any variations. Some items may be sold individually or in sets, and images may occasionally depict additional products or quantities not included in your purchase. For assistance or clarification, please contact customer support.

Specifications

Reference Information

Reference Data (Provide these details to our support team)
Brand Name/s Holley, Hilborn, Holley Efi, Retrobright, Terminator X
StreetFX SKU hly558-126
SFX Item ID 4782245
Accounting SKU hly-558-126
Manufacturer SKU 558-126
Manufacturer UPC 090127054857
Alternative References 558-126, HLY-558-126, HOL558-126

Wiring Harnesses, Holley EFI, Main Harness, Unterminated, Flying Lead, 15 ft. Long, J1A/J1B Connectors, Plug Seals Included, Universal, Each

Want to fully rewire your Holley EFI installation? Or perhaps you're starting a new build, and want to wire everything perfectly the first time. Holley EFI unterminated main harnesses come with both J1A and J1B connectors fully terminated—with 15 ft. of flying lead wiring to allow you to completely customize your main harness installation.

Features include:
• J1A and J1B terminated connectors
• 60 crimped wires: (57 of 20-gauge wire, and three 18-gauge wire)
• 15 ft. long flying lead harness
• 30 optional plug seals

Product Attributes
BrandHolley
Manufacturer's Part Number558-126
Part TypeWiring Harnesses
Product LineHolley EFI Unterminated Main Harnesses
UPC090127054857
Harness LengthExtra-long
Fuse Block IncludedYes
QuantitySold individually.
NotesThis unterminated harness features both J1A and J1B connectors fully terminated with 15 ft. of flying lead wire and 30 optional plug seals.

Compatibility

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