Holley
Wire Harness Kit - EFI Terminator I/O
SKU: H00E 558-420
Description
Part #: 558-420
PN 558-420 contains 5 extra input/output wires that the base Terminator EFI harness does not contain. It contains Input wires for Inputs 1-4. It contains one wire for Output 2. These inputs and outputs can perform features and functions that must be programmed via Holley EFI laptop software. The software also contains instructions on how to program these.
This kit contains 4 extra input wires and 1 extra output wire that the base Terminator EFI harness does not contain.
Fitment
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Available on iOS & Android
Specifications
| Brand | Holley |
| Part Number | H00E 558-420 |
| Weight | 0.6 lb |
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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