Street. Track. Everything between.
Your garage Find parts for your vehicle Select year, make and model to narrow your search.

Holley

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

Holley

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$946.91
LOW STOCK! Est Ship 4-7 days. HURRY! LOW STOCK. This item is in limited stock at one of our distribution centres. The ETA is the approximate time required to prepare your order for dispatch.
View cart
We accept
American Express
Mastercard
Visa
PayPal Checkout
Direct Deposit
Afterpay
Apple Pay
Google Pay
Zip Pay

Description

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

Part Type

Flying Lead Main Harness

Data: v4.2 - Upd: 2026-10-13 18:48:28

Specifications

Product Attributes - Brand
Holley
Product Attributes - Manufacturer's Part Number
558-126
Product Attributes - Part Type
Wiring Harnesses
Product Attributes - Product Line
Holley EFI Unterminated Main Harnesses
Product Attributes - UPC
090127054857
Product Attributes - Harness Length
Extra-long
Product Attributes - Fuse Block Included
Yes
Product Attributes - Quantity
Sold individually.
Product Attributes - Notes
This unterminated harness features both J1A and J1B connectors fully terminated with 15 ft. of flying lead wire and 30 optional plug seals.

Reference Information

Brand Name/s Holley
StreetFX SKU hly558-126
SFX Item ID 4782245
Supplier Item Code 4782245
Manufacturer SKU 558-126
Manufacturer UPC 90127054857
Alternative References HOL558-126, J1A/J1B

Compatibility

Application Data
  • UniversalYes
    Application NotesThis unterminated harness features both J1A and J1B connectors full terminated with 15 ft. of flying lead wire and 30 optional plug seals.

Loading compatibility information...

Keep shopping

More from Holley