Availability
Holley EFI Systems Main Wiring Harnesses
Not Yet Reviewed
Showing In Stock Items. Show All 8 Items.
Fuel Injection System Components, Holley EFI, Main Harness, Plug-and-Play, Factory PWM/IAC Connectors, with OE Injectors, Ford, Mustang, 5.0L, Each
Part Number: HLY-558-128
Not Yet Reviewed
Estimated Ship Date: Today
Estimated Ship Date: Today
This product may not be eligible for select promotional offers
Wiring Harnesses, Holley EFI, LT4 Engine, Main Harness, for Terminator X, V3 ECU, Cadillac, Chevy, Each
Part Number: HLY-558-130
Not Yet Reviewed
Estimated Ship Date: Today
Estimated Ship Date: Today
This product may not be eligible for select promotional offers
Wiring Harnesses, Holley EFI, Coyote, with TI-VCT/Stock Coils, Main Harness, MPFI, for HP, Dominator, EFI Systems, Ford, 5.0L, Each
Part Number: HLY-558-110
Not Yet Reviewed
Estimated Ship Date: Today
Estimated Ship Date: Today
This product may not be eligible for select promotional offers
Wiring Harnesses, Holley EFI, Main Harness with Smart Coils, 7.3L Godzilla, Ford Each
Part Number: HLY-558-141
Not Yet Reviewed
Estimated Ship Date: Mar 2, 2026 if ordered today
Estimated Ship Date: Mar 2, 2026 if ordered today
This product may not be eligible for select promotional offers
Fuel Injection System Wiring Harnesses, Holley EFI, Includes Stealth Ram/TPI Main, Power, Injector Harnesses, for HP, Dominator ECU, Chevrolet, Kit
Part Number: HLY-558-503
Not Yet Reviewed
Estimated Ship Date: Mar 2, 2026 if ordered today
Estimated Ship Date: Mar 2, 2026 if ordered today
This product may not be eligible for select promotional offers
Fuel Injection System Wiring Harnesses, Holley EFI, Coyote Ti-VCT, Main Harness, Plug-and-Play, Drive-by-Wire, with Holley Smart Coils, Ford, 5.0L Kit
Part Number: HLY-558-122
Not Yet Reviewed
Estimated Ship Date: Mar 2, 2026 if ordered today
Estimated Ship Date: Mar 2, 2026 if ordered today
This product may not be eligible for select promotional offers
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Main Harness, Terminator X, Terminator Max X Systems, Ford, Mustang, 5.0L, Each
Part Number: HLY-558-513
Not Yet Reviewed
Estimated Ship Date: Mar 2, 2026 if ordered today
Estimated Ship Date: Mar 2, 2026 if ordered today
This product may not be eligible for select promotional offers
Wiring Harnesses, Holley EFI, Main Harness with Stock Coils, 7.3L Godzilla, Ford Each
Part Number: HLY-558-140
Not Yet Reviewed
Estimated Ship Date: Today
Estimated Ship Date: Today
This product may not be eligible for select promotional offers
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