Fuel Injection System Wiring Harnesses - No Stock EFI System

Holley Replacement Fuel Injector Wiring Harnesses 558-501

Fuel Injection System Wiring Harnesses, Holley EFI, GM LS 58X Crank Sensor, Includes Power, EV6 Injector, Main Harnesses, for HP, Dominator ECUs, Kit

Part Number: HLY-558-501

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley EFI Systems Wiring Harnesses 558-108

Wiring Harnesses, Holley EFI, Ford 2V/4V Modular, Main Harness, Multi-port Fuel Injection, for HP, Dominator, EFI Systems, Ford, 4.6-5.4L, Each

Part Number: HLY-558-108

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

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

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley EFI Systems Wiring Harnesses 558-508

Fuel Injection System Wiring Harnesses, Holley EFI, Ford V8, Universal MPFI, with Main, Power, Injector Harnesses, for HP, Dominator ECU, Kit

Part Number: HLY-558-508

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

Holley EFI Systems Wiring Harnesses 558-306

Fuel Injection System Wiring Harnesses, Holley EFI, Unterminated, Ignition Harness, with Pins, Seals, Connector, for HP, Dominator EFI Systems, Kit

Part Number: HLY-558-306

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley Drive-By-Wire Throttle Body Wiring Harnesses 558-418

Fuel Injections System Wiring Harnesses, Gen III Hemi, Drive-By-Wire Harness, Late Pedal, OE Connectors, Plug-and-Play, Chrysler, Dodge, Jeep, Kit

Part Number: HLY-558-418

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

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: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

Holley EFI Systems Main Wiring Harnesses for 2011-2017 F-150, MUSTANG - 558-110

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: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

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 )

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley EFI Systems Wiring Harnesses 558-101

Wiring Harnesses, Holley EFI, Replacement Harness, Multi-Port, Speed Density Metered, for Avenger, HP, Dominator, EFI Systems, with Stealth Ram, Each

Part Number: HLY-558-101

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

FAST XFI Fuel Injector Harnesses 301200

Wiring Harness, Fuel Injector, FAST XFI, Chevy, 18436572 Firing Order, Each

Part Number: FST-301200

Not Yet Reviewed

Estimated Ship Date: Dec 28, 2026 if ordered today

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Estimated Ship Date: Dec 28, 2026 if ordered today

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

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley Main Power Harnesses 558-319

Fuel Injection System Wiring Harnesses, Holley EFI, Main Power Harness, Coyote Ti-VCT, Plug-and-Play, for Dominator/HP EFI Systems, Ford, 5.0L, Each

Part Number: HLY-558-319

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley EFI Systems Wiring Harnesses 550-616N

Engine Management Systems, HP EFI, ECU and Harness, Up to 16-Injectors, 8-Coils, NTK O2, Wideband, Ford, Lincoln, Mercury, 2-valve, 4.6L, 5.4L, Kit

Part Number: HLY-550-616N

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

Holley Drive-By-Wire Throttle Body Wiring Harnesses 558-437

Fuel Injection System Wiring Harnesses, Holley EFI, Hemi Drive-By-Wire, Throttle Body Harness, for Holley Dominator EFI Only, Dodge, 5.7-6.4L, Each

Part Number: HLY-558-437

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

Haltech Nexus Rebel LS Injector Sub-Harnesses HT-186501

Wiring Harness, Fuel Injector Sub-Harness, EV1, Nexus Rebel LS, Chevrolet, LS, Each

Part Number: HTH-HT-186501

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

Holley Replacement Fuel Injector Wiring Harnesses 558-207

Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Injector Harness, Unterminated Base, Bosch EV1 Style, with Connector, 16-piece, Set

Part Number: HLY-558-207

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

Holley EFI Systems Main Wiring Harnesses 558-141

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: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

FAST XFI Fuel Injector Harnesses 301204

Wiring Harness, Fuel Injector, FAST XFI, Ford, Each

Part Number: FST-301204

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

FiTech TPS Splitter Harnesses 62020

Fuel Injection System Wiring Harnesses, FiTech, EFI, TPS Splitter, Gm 3 Pin, Each

Part Number: FIF-62020

Not Yet Reviewed

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

FAST Idle Air Control Harness Adapters 308023

Harness Adapter, IAC to FAST EFI, Chevy, Pontiac, Each

Part Number: FST-308023

4.75 out of 5 stars ( 4 )

Estimated Ship Date: Monday 10/26/2026 if shipped by air

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Estimated Ship Date: Monday 10/26/2026 if shipped by air

FAST XFI Fuel Injector Harnesses 301201

Wiring Harness, Fuel Injector, FAST XFI, Chevy, 18736542 Firing Order, Each

Part Number: FST-301201

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Dec 28, 2026 if ordered today

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Estimated Ship Date: Dec 28, 2026 if ordered today

Holley EFI Systems Wiring Harnesses 558-502

Fuel Injection System Wiring Harnesses, Holley EFI, GM LS 58X Crank Sensor, Power, Bosch Injector, Main Harnesses, for HP, Dominator ECUs, Kit

Part Number: HLY-558-502

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today

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: Nov 12, 2026 if ordered today

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Estimated Ship Date: Nov 12, 2026 if ordered today

Holley Terminator Stealth 2x4 Primary Throttle Body Sub Harnesses 558-459

Fuel Injection System Wiring Harnesses, Holley EFI, Terminator Stealth 2X4, Primary Throttle Body Sub Harness, Pre-Terminated, Plug-and-Play, Each

Part Number: HLY-558-459

Not Yet Reviewed

Estimated Ship Date: Nov 11, 2026 if ordered today

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Estimated Ship Date: Nov 11, 2026 if ordered today