Sale

Ignitions and Electrical› Wiring Harnesses

Holley

HARNESS KIT, UNIVERSAL V8 MPFI

$979.95 $898.15 Save $81.80

SKU: H00E 558-504

In Stock
In Stock
Ships by Jun 7
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

An EFI system depends heavily on being supplied a clean and constant voltage source. The grounds of an electrical system are just as important as the power side. Our Holley EFI Harness Kit for your GM LS engine comes complete with the main harness, power harness and injector harness to support your primary system! Features: • Harness Kit Includes; Main Power Harness, LS1 Main Harness & V-8 Injector harness • Simple Installation • Works with HP or Dominator ECUs.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandHolley
Part NumberH00E 558-504
Weight5.55 lb

Buy with Confidence

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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