Availability
Showing In Stock Items. Show All 49 Items.
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, LSX Injector Harness, EV6 Style, for HP, Dominator, Terminator EFI Systems, Each
Part Number: HLY-558-201
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
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Fuel Injection System Wiring Harnesses, EFI CAN Splitters, 12 in. Length, for Use with Holley Terminator X or Sniper EFI Systems, Each
Part Number: SUM-890520
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Wiring Harnesses, Holley EFI, Replacement, LS Style, 58X/4X Main Harness, Speed Density, for HP, Dominator, EFI Systems Only, Chevy, 6.0-7.0L, Each
Part Number: HLY-558-103
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, CAN Splitter Assembly, Pre-Terminated, Plug-and-Play, for Terminator X, Sniper EFI Systems, Each
Part Number: HLY-558-465
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harness, Holley EFI, Main Power, Universal, Speed Density/Throttle, 13 ft. Long, for Avenger, HP, Dominator EFI, Kit
Part Number: HLY-558-308
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection Systems Wiring Harnesses, Dominator EFI, J2A Auxiliary Harness, MPFI, Speed Density/Throttle Metered, with Wideband O2 Sensor, Kit
Part Number: HLY-558-401
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection Systems Wiring Harnesses, Dominator EFI, J2B Auxiliary Harness, 8 Additional Inputs, 23 Outputs, Connector Included, Kit
Part Number: HLY-558-402
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, CAN Adapter Harness, Male to Female Adapter, 48 in. Long, for Racepak or CAN Device, Each
Part Number: HLY-558-452
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Drive-by-wire Harness, GM LSx Early Truck, MPFI, SFI, TBI, for Dominator EFI Systems, Each
Part Number: HLY-558-429
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Wiring Harnesses, Holley EFI, TFI Ignition, Adapter Harness, for Avenger, HP, Dominator EFI Systems, Each
Part Number: HLY-558-305
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection Systems Wiring Harnesses, Dominator EFI, J4 Auxiliary Harness, MPFI, Speed Density/Throttle, 26 Input/Outputs, Connector Included, Kit
Part Number: HLY-558-404
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Main Harness, Terminator EFI Systems, Model 550-405, 550-406, Each
Part Number: HLY-558-414
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Wiring Harnesses, Holley EFI, Main Harness, 58X LS TBI, for Terminator, Terminator Stealth, Throttle Body Systems, Chevy, Each
Part Number: HLY-558-112
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection Systems Wiring Harnesses, Dominator EFI, J3 Auxiliary Harness, MPFI, Speed Density/Throttle, 17 Input/Outputs, Connector Included, Kit
Part Number: HLY-558-403
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, MPFI, Mass Airflow, Injector Harness, LS Multec 2, Chevy, Truck, 4.8-6.0L, Each
Part Number: HLY-558-214
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Wiring Harnesses, Holley EFI, Ford 2V/4V Modular, Main Harness, Multi-Port Fuel Injection, for Holley Smart Coils, HP EFI System, Ford, 4.6-5.4L, Each
Part Number: HLY-558-113
Not Yet Reviewed
Estimated Ship Date: Jan 22, 2026 if ordered today
Estimated Ship Date: Jan 22, 2026 if ordered today
Wiring Harnesses, Holley EFI, HEI Distributor, Adapter Harness, Small Cap, Computer Controlled, for Avenger, HP, Dominator EFI Systems, Each
Part Number: HLY-558-304
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Ford Coyote, Drive-By-Wire Harness, Multi-port Style, for HP/Dominator EFI System, Ford, 5.0L, Kit
Part Number: HLY-558-422
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, EFI CAN Splitters, 48 in. Length, for Use with Holley Terminator X or Sniper EFI Systems, Each
Part Number: SUM-890521
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Dominator EFI, GM LSx, Dual Drive-by-Wire Harness, for Throttle Bodies to Dominator EFI Systems, Each
Part Number: HLY-558-411
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Gen III Hemi, Injector Harness, Stock/USCAR Injectors, for HP, Dominator EFI, Each
Part Number: HLY-558-210
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Injector Driver harness, Plug-and-Play, MPFI, JB2 Connector, for Dominator ECU, Each
Part Number: HLY-558-219
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Ford V8, Injector Harness, Multi-Port, for HP, Dominator EFI Systems, Each
Part Number: HLY-558-209
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
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: Jan 22, 2026 if ordered today
Estimated Ship Date: Jan 22, 2026 if ordered today
Wiring Harnesses, Holley EFI, Gen III Hemi, Throttle Position, Idle Air Controls, Factory Connectors, Chrysler, Dodge, Jeep, Hemi, Late Model, Each
Part Number: HLY-558-116
Not Yet Reviewed
Estimated Ship Date: Monday 1/5/2026
Estimated Ship Date: Monday 1/5/2026
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