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Holley

Terminator X ECU Kit for LS Engines

Name: Terminator X ECU Kit for LS Engines
Brand: Holley
SKU: HOL-550-659

$3,449.95 $3,346.45 Save $103.50

SKU: HOL-550-659

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Overview

It features extensive inputs and outputs for limitless combinations and includes a two-channel knock control sensor. The kit comes with the Dominator ECU, USB cable, ECU power harness, engine main harness, and EV1 injector harness.

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The Holley 550-659 Dominator EFI Kit provides a comprehensive solution for managing your GM LS-Series engine's fuel and ignition. It offers self-tuning capabilities, allowing for easier calibration and optimization of engine performance. Specifically engineered for GM LS 58x crank and 4x cam applications, this kit is compatible with 4.8L, 5.3L, and 6.0L style engines. It utilizes EV1 injectors and is designed to work with a DBW throttle body, ensuring seamless integration with modern electronic throttle systems. The Dominator EFI system is intended for non-emissions street and racing engine applications, offering advanced features for performance tuning. This kit is designed for specific engine configurations, fitting GM LS 58x Crank, 4x Cam - 4.8/5.3/6.0 style Engines with EV1 Injectors, and a DBW Throttle Body. While the Dominator EFI system offers extensive control, it's important to note that it is intended for non-emissions applications.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

Brand	Holley
Part Number	HOL-550-659
Category	Air and Fuel

Videos

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Returns & Fitment

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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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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