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ECU Extension Harnesses for Holley EFI

 

 
Our Holley EFI ECU Extension Harnesses are made by EFI Conversions with the same quality crimped connections and connectors Holley EFI uses. We are the premier online store for extensions, allowing you to choose the length you need to custom order your extensions.

See also our list of Custom-Length Pigtails for Holley EFI

19 products
  • J1A 34-pin Extension Harness for Holley EFI Terminator X GM Gen V LT GDI ECU
    $116.70
    $97.20
  • J1B 26-pin Extension Harness for Holley EFI Terminator X GM Gen V LT GDI ECU
    $108.90
    $90.70
  • Holley Terminator X Max ECU 34 Pin J1A (P1A) Extension Harness
    $93.60
    $77.99
  • Holley Dominator ECU 34 Pin J2A (P2A) Extension Harness
    $93.40
    $77.80
  • Holley Dominator ECU 34 Pin J2A (P2A) Extension Harness
    $93.40
    $77.80
  • Holley Terminator X ECU 34 Pin J1A (P1A) Extension Harness
    $93.30
    $77.70
  • Holley HP ECU 34 Pin J1A (P1A) Extension Harness
    $93.30
    $77.70
  • Holley Dominator ECU 34 Pin J1A (P1A) Extension Harness
    $93.30
    $77.70