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Wiring Harnesses & Connectors

Wiring Harnesses, Connectors & Electrical Assembly Components A clean, correctly specified electrical system is one of the foundations of a reliable performance vehicle. Poor electrical connections — whether through incorrect wire gauge, inadequate insulation, corroded terminals, or improvised connections —...

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Wiring Harnesses & Connectors
  • ✓ In Stock
    Photo - Primary
    Earl's at992410erl

    Earl's -10 AN Bulkhead Nut

    Available for Any Plumbing Situation And Many Custom...

    Part TypeElectrical Bulkhead Connector
    £8.99 inc VAT
    £7.49 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's at992408erl

    Earl's -8 AN Bulkhead Nut

    Available for Any Plumbing Situation And Many Custom...

    Part TypeElectrical Bulkhead Connector
    £10.99 inc VAT
    £9.16 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's at592406erl

    Earl's -6 AN Bulkhead Nut

    Available for Any Plumbing Situation And Many Custom...

    Part TypeElectrical Bulkhead Connector
    £11.99 inc VAT
    £9.99 ex VAT
  • ⏳ Backorder
    Photo - Primary
    Earl's at592404erl

    Earl's -4 AN Bulkhead Nut

    Available for Any Plumbing Situation And Many Custom...

    Part TypeElectrical Bulkhead Connector
    £8.99 inc VAT
    £7.49 ex VAT
  • ⏳ Backorder
    Photo - Primary
    Earl's at592403erl

    Earl's -3 AN Bulkhead Nut

    Available for Any Plumbing Situation And Many Custom...

    Part TypeElectrical Bulkhead Connector
    £10.99 inc VAT
    £9.16 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's 992410erl

    Earl's -10 AN Bulkhead Nut

    Blue Anodized Lightweight Aluminum Construction. Available for Any...

    Part TypeElectrical Bulkhead Connector
    £8.99 inc VAT
    £7.49 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's 992408erl

    Earl's -8 AN Bulkhead Nut

    Blue Anodized Lightweight Aluminum Construction. Available for Any...

    Part TypeElectrical Bulkhead Connector
    £10.99 inc VAT
    £9.16 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's 592406erl

    Earl's -6 AN Bulkhead Nut

    Blue Anodized Lightweight Aluminum Construction. Available for Any...

    Part TypeElectrical Bulkhead Connector
    £13.00 inc VAT
    £10.83 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's 592404erl

    Earl's -4 AN Bulkhead Nut

    Blue Anodized Lightweight Aluminum Construction. Available for Any...

    Part TypeElectrical Bulkhead Connector
    £8.99 inc VAT
    £7.49 ex VAT
  • ✓ In Stock
    Photo - Primary
    Earl's 592403erl

    Earl's -3 AN Bulkhead Nut

    Blue Anodized Lightweight Aluminum Construction. Available for Any...

    Part TypeElectrical Bulkhead Connector
    £10.99 inc VAT
    £9.16 ex VAT
  • ⏳ Backorder
    Earl's 502403ERL primary image
    Earl's 502403erl

    Earl's -3 Bulkhead Nut

    Electroless Nickel Plated Domestic Steel Construction. Available for...

    Part TypeElectrical Bulkhead Connector
    £14.99 inc VAT
    £12.49 ex VAT
  • ✓ In Stock
    Holley EFI F6 Split Wire Loom - 3/4 Inch
    Holley EFI 573-109

    Holley EFI F6 Split Wire Loom - 3/4 Inch

    50 Feet, Black, 3/4" Braided F6 Split Wire...

    Part TypeWiring Harness
    £146.99 inc VAT
    £122.49 ex VAT
  • ✓ In Stock
    Holley EFI F6 Split Wire Loom - 3/4 Inch
    Holley EFI 573-108

    Holley EFI F6 Split Wire Loom - 3/4 Inch

    10 Feet, Black, 3/4" Braided F6 Split Wire...

    Part TypeWiring Harness
    £34.99 inc VAT
    £29.16 ex VAT
  • ✓ In Stock
    Holley EFI F6 Split Wire Loom - 1/2 Inch
    Holley EFI 573-107

    Holley EFI F6 Split Wire Loom - 1/2 Inch

    50 Feet, Black, 1/2" Braided F6 Split Wire...

    Part TypeWiring Harness
    £112.00 inc VAT
    £93.33 ex VAT
  • ✓ In Stock
    Holley EFI F6 Split Wire Loom - 3/8 Inch
    Holley EFI 573-105

    Holley EFI F6 Split Wire Loom - 3/8 Inch

    50 Feet, Black, 3/8" Braided F6 Split Wire...

    Part TypeWiring Harness
    £92.99 inc VAT
    £77.49 ex VAT
  • ✓ In Stock
    Holley EFI 100FT Shielded Cable, 3 Conductor
    Holley EFI 572-104
    Part TypeBulk Wire
    £175.99 inc VAT
    £146.66 ex VAT
  • ✓ In Stock
    Holley EFI 25FT Shielded Cable, 3 Conductor
    Holley EFI 572-103
    Part TypeBulk Wire
    £49.99 inc VAT
    £41.66 ex VAT
  • ✓ In Stock
    Holley EFI 100FT Cable, 7 Conductor - 7 conductor cable
    Holley EFI 572-101
    Part TypeBulk Wire
    £262.00 inc VAT
    £218.33 ex VAT
  • ✓ In Stock
    Holley EFI 25FT Cable, 7 Conductor - 7 conductor cable
    Holley EFI 572-100
    Part TypeBulk Wire
    £92.99 inc VAT
    £77.49 ex VAT

Wiring Harnesses, Connectors & Electrical Assembly Components

A clean, correctly specified electrical system is one of the foundations of a reliable performance vehicle. Poor electrical connections — whether through incorrect wire gauge, inadequate insulation, corroded terminals, or improvised connections — cause intermittent faults that are among the most frustrating and time-consuming problems to diagnose in any vehicle. Quality wiring harnesses, pre-terminated connectors, and correctly rated bulk wire eliminate these issues from the start, producing an electrical system that functions correctly from first startup and continues to do so reliably throughout the vehicle's life.

With 73 electrical assembly products from Holley EFI, Earl's, ACCEL, and BP Automotive, our wiring range covers engine wiring harnesses for LS and EFI applications, bulk wire for custom harness construction, connectors and seals for weatherproof connections, and the specialised components required for professional-quality electrical installations.

Engine Wiring Harnesses — Plug-and-Play Installation

A quality engine wiring harness eliminates the most challenging aspect of an LS swap or EFI conversion — the wiring. Pre-terminated, colour-coded, and labelled harnesses designed for specific engine and ECU combinations connect directly to the engine's sensors, actuators, and management system with correct connector types and wire gauges, eliminating the need to source individual connectors and build connections from scratch. Our harness range covers popular LS engine and standalone ECU combinations for the most common swap applications.

Bulkhead Connectors and Firewall Penetrations

Bulkhead connectors allow clean, weatherproof routing of wiring through the firewall between the engine bay and interior — avoiding the improvised grommets and individual wire penetrations that characterise less carefully built vehicles. A quality bulkhead connector presents a professional appearance, maintains the firewall's noise and vapour barrier, and provides a positive, weatherproof connection at the critical firewall junction.