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Replacement Parts for HLY-550-1221
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Oxygen Sensors, Holley EFI, Replacement, O2 Sensor, Bosch LSU Style, 3-wire, Thread-in, Wire Harness, for Sniper EFI or Terminator X Systems, Each
Part Number: HLY-554-155
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Engine Management Systems, Holley EFI, Terminator X, Controls 8-Injectors, 8-Coils, Analog Input/Outputs, Wideband, CANBUS, Chevy, Ford, Dodge, Each
Part Number: HLY-554-152
Not Yet Reviewed
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
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 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Wiring Harnesses. Holley EFI, Replacement, Wideband O2 Adapter Harness, Terminator EFI Systems, Pre-Terminated, Plug-and-Play, Each
Part Number: HLY-558-463
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Wiring Harnesses. Holley EFI, Replacement, Input/Output Harness, Terminator EFI Systems, Pre-Terminated, Plug-and-Play, Each
Part Number: HLY-558-462
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Fuel Injection System Wiring Harnesses, Holley EFI, Replacement, Ford V8, Evenly Spaced, Injector Harness, USCAR/EV6, for HP, Dominator EFI, Each
Part Number: HLY-558-212
Not Yet Reviewed
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
MAP Sensor Adapters, Replacement, Quick Turn Adapters, 1/8 in., 3/16 in. 1/4 in., for Terminator X, Each
Part Number: HLY-543-121
Not Yet Reviewed
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Bungs, Nuts, and Fittings, Weld-In, Oxygen Sensor Bung, Steel, 18mm x 1.5, Female Thread, Each
Part Number: HLY-534-49
Estimated Ship Date: Monday 10/19/2026 if shipped by air
Estimated Ship Date: Monday 10/19/2026 if shipped by air
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 3, 2026 if ordered today
Estimated Ship Date: Nov 3, 2026 if ordered today
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