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Holley EFI Systems Wiring Harnesses 558-305

Wiring Harnesses, Holley EFI, TFI Ignition, Adapter Harness, for Avenger, HP, Dominator EFI Systems, Each

Part Number: HLY-558-305

4.9 out of 5 stars ( 10 )

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Holley Dominator EFI Auxiliary Harnesses 558-404

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

4.0 out of 5 stars ( 1 )

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Holley EFI Systems Wiring Harnesses 558-414

Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Main Harness, Terminator EFI Systems, Model 550-405, 550-406, Each

Part Number: HLY-558-414

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Holley Terminator EFI Wiring Harnesses 558-420

Fuel Injection System Wiring Harnesses, Holley EFI, Auxiliary Input/Output Harness, Terminator EFI, Gains 4 Inputs/1 Output, Each

Part Number: HLY-558-420

5.0 out of 5 stars ( 2 )

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Holley Sniper HyperSpark Plug-and-Play Main Wiring Harnesses 558-328

Wire Harnesses, Sniper EFI, HyperSpark, Main Harness, Throttle Body Injection, Plug-n-Play, 40 amp Relay Included, Each

Part Number: SNE-558-328

5.0 out of 5 stars ( 2 )

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Holley EFI Systems Wiring Harnesses 558-117

Fuel Injection System Wiring Harnesses, Holley EFI, Multi-port Fuel Injection, Coil-on-Plug, Dual CANbus, for Holley HP, Dominator EFI, Universal, Kit

Part Number: HLY-558-117

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Holley EFI Systems Wiring Harnesses 558-116

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

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Holley EFI Systems Wiring Harnesses 558-112

Wiring Harnesses, Holley EFI, Main Harness, 58X LS TBI, for Terminator, Terminator Stealth, Throttle Body Systems, Chevy, Each

Part Number: HLY-558-112

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Holley Dominator EFI Auxiliary Harnesses 558-403

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

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Holley Replacement Fuel Injector Wiring Harnesses 558-214

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

5.0 out of 5 stars ( 3 )

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Holley EFI Pro Dash Input/Output Harnesses 558-456

Fuel Injection System Wiring Harnesses, Holley EFI, Pro-Dash, Input/Output, Unterminated, 2 and 3 Conductor Cable, 10 ft. Long, Pins, Plugs, Each

Part Number: HLY-558-456

5.0 out of 5 stars ( 1 )

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Holley EFI Systems Wiring Harnesses 558-113

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 21, 2026 if ordered today

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Estimated Ship Date: Jan 21, 2026 if ordered today

Holley EFI Systems Wiring Harnesses 558-204

Fuel Injection System Wiring Harnesses, Holley EFI, Fuel Injector Harness, Unterminated, Bosch Style, for HP, Dominator EFI Systems, Universal, Each

Part Number: HLY-558-204

3.0 out of 5 stars ( 1 )

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Holley GM Distributor Wiring Harness Adapters 558-304

Wiring Harnesses, Holley EFI, HEI Distributor, Adapter Harness, Small Cap, Computer Controlled, for Avenger, HP, Dominator EFI Systems, Each

Part Number: HLY-558-304

5.0 out of 5 stars ( 2 )

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Holley EFI Terminator Stealth Main Wiring Harnesses 558-121

Fuel Injection System Wiring Harnesses, Holley EFI, Terminator Stealth 2x4, Upgrade Main Harness, Plug-and-Play, Universal, Kit

Part Number: HLY-558-121

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Holley EFI CAN Adapter Harnesses 558-430

Fuel Injection Wiring Harnesses, Holley EFI, CAN Adapter/Power Harness, Pre-Terminated, Plug-and-Play, 2-Pin Holley to 4-Pin CAN Device, Each

Part Number: HLY-558-430

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Holley Replacement Fuel Injector Wiring Harnesses 558-210

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

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Holley Drive-By-Wire Throttle Body Wiring Harnesses for 2011-2014 F-150, MUSTANG - 558-422

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

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Summit Racing™ EFI CAN Splitters SUM-890521

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

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Holley EFI Benchtop Harnesses 558-127

Wiring Harnesses, Holley EFI, Benchtop Harness, Test Harness, EFI Input Connectors, Power Switch, for HP, Dominator, Terminator, Sniper ECUs, Each

Part Number: HLY-558-127

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Holley EFI Systems Wiring Harnesses 558-411

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

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Holley Replacement Fuel Injector Wiring Harnesses 558-219

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

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Holley Replacement Fuel Injector Wiring Harnesses 558-209

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

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Holley Replacement Fuel Injector Wiring Harnesses 558-216

Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, EV6 Unterminated, Injector Harness, 36 in. Long, with Pins, Seals, Connector, Kit

Part Number: HLY-558-216

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Holley EFI Systems Main Wiring Harnesses for 2011-2017 F-150, MUSTANG - 558-122

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 21, 2026 if ordered today

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Estimated Ship Date: Jan 21, 2026 if ordered today