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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
  • Holley Terminator X Max ECU 26 Pin J4 (P4) GM 4L60E 4L80E Transmission Extension Harness
    $90.80
    $75.60
  • Holley Terminator X Max 26 Pin J4 (P4) GM 6L80E 6L90E Transmission Extension Harness
    $90.80
    $75.60
  • Holley Dominator ECU 26 Pin J4 (P4) 4L60E 4L80E Transmission Extension Harness
    $90.80
    $75.60
  • Holley Dominator ECU 26 Pin J2B (P2B) Extension Harness
    $90.80
    $75.60
  • Holley Terminator X Max ECU 26 Pin J1B (P1B) Extension Harness
    $90.60
    $75.50
  • Holley HP ECU 26 Pin J1B (P1B) Extension Harness
    $90.60
    $75.50
  • Holley Dominator ECU 26 Pin J1B (P1B) Extension Harness
    $90.60
    $75.50
  • Holley Terminator X Max ECU 26 Pin J3 (P3) Drive by Wire Extension Harness
    $90.50
    $75.40