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    Sale!

    Holley EFI Holley EFI Terminator X - Gen IV 4.8/5.3/6.0 GM Truck Engines and LS2/LS3 550-905

    Vendor: Holley EFI
    SKU: GVMR_550-905
    Save $132
    Sale Price $1,499.95 Regular Price $1,631.95
    Fast Fulfillment: In-stock parts typically ship same day or next business day.
    Free Shipping on Orders Over $99 | Excludes freight shipments
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    Terminator X features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Terminator X comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast. The 3.5" touch screen LCD handheld contains an easy to use calibration wizard as well as tuning and gauge display functions. Also included is Holley EFI's industry-leading, easy-to-use software suite that allows full laptop access for advanced users. Whether you are building a budget beater or a boosted race car, Terminator X has the features and technology you need at a price that won't break the bank.


    Holley EFI Holley EFI Terminator X - Gen IV 4.8/5.3/6.0 GM Truck Engines and LS2/LS3 550-905


    Specifications:

    10429 Yes
    10431 Yes
    Brand Holley EFI
    10423 Yes
    Category Fuel Injection - EFI
    10438 Yes
    Crank Reluctor 58x
    10430 Yes
    10437 No
    Drive-By-Wire No
    10442 Yes
    10418 Yes
    10428 Yes
    Emission Code 3
    Engine Gen IV GM LS
    10433 Yes
    7246 No
    10417 No
    906 No
    10425 No
    8922 No
    3390 Performance
    Handheld Included Yes
    909 No
    10422 Yes
    Ignition Type GM LS 58x
    10432 Yes
    Injector Connector USCAR (EV6)
    9780 No
    10427 Yes
    MAP Sensor 1bar
    30 No
    10420 Yes
    Product Type EFI System
    10421 Yes
    10434 Yes
    Terminator LS Options Fuel, Spark
    918 No
    Transmission None
    10435 Yes
    Warning California Proposition 65
    10419 Yes
    10429 Yes
    10431 Yes
    Brand Holley EFI
    10423 Yes
    Category Fuel Injection - EFI
    10438 Yes
    Crank Reluctor 58x
    10430 Yes
    10437 No
    Drive-By-Wire No
    10442 Yes
    10418 Yes
    10428 Yes
    Emission Code 3
    Engine Gen IV GM LS
    10433 Yes
    7246 No
    10417 No
    906 No
    10425 No
    8922 No
    3390 Performance
    Handheld Included Yes
    909 No
    10422 Yes
    Ignition Type GM LS 58x
    10432 Yes
    Injector Connector USCAR (EV6)
    9780 No
    10427 Yes
    MAP Sensor 1bar
    30 No
    10420 Yes
    Product Type EFI System
    10421 Yes
    10434 Yes
    Terminator LS Options Fuel, Spark
    918 No
    Transmission None
    10435 Yes
    Warning California Proposition 65
    10419 Yes
    Description_INV TERMINATOR X MPFI, LS2/LS3 & LATE TRUCK
    Description_ASC Terminator X ECU's are designed to be mounted with the LED's facing up.
    Description_DES Holley EFI Terminator X - Gen IV 4.8/5.3/6.0 GM Truck Engines and LS2/LS3
    Description_EXT 58x Crank - 4x Cam - EV6 Injectors - 3.5 in. Touchscreen
    Description_MKT Take control of your LS engine with Terminator X. Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley EFI at a budget-friendly price.
    Description_MKT Terminator X features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Terminator X comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast. The 3.5" touch screen LCD handheld contains an easy to use calibration wizard as well as tuning and gauge display functions. Also included is Holley EFI's industry-leading, easy-to-use software suite that allows full laptop access for advanced users. Whether you are building a budget beater or a boosted race car, Terminator X has the features and technology you need at a price that won't break the bank.
    Description_FAB Designed for GM LS Engines with 58x Crank, 4x Cam - and EV6 Injectors
    Description_FAB Real-Time fuel map learn takes the guess work out of tuning your base fuel table
    Description_FAB High Impedance Injector Drivers will safely power most Stock LS injectors and Holley EFI Injectors; injector support chart provided in the instructions (will not control Low Impedance Injectors)
    Description_FAB All of the new Terminator X systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control
    Description_FAB MAP Sensor vacuum hose adapters (1/8th – ¼ and 3/16ths)
    Description_FAB 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, activation triggers for nitrous activation, or a trans brake
    Description_FAB 4 Outputs – Ground, PWM - for accessories such as fans, boost control, nitrous control, IAC Kit, and more
    Description_FAB Boost Control – Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
    Description_FAB Nitrous Control – Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
    Description_FAB On-Board Diagnostic LEDS for: ECU Power – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allows you to identify any Critical engine issues at a glance
    Description_FAB Advanced Tables – 4x 1D Tables, 1x 1D per Gear Table, 4x 2D Tables, 1x 2D per Gear Table can be used for any custom tables you can dream up, such as Flex Fuel Sensor Offset Table, or a custom fuel or oil pressure safety
    Description_FAB The included 3.5" Touchscreen Handheld contains a calibration wizard, that allows you to quickly build a base tune for any LS engine. Additionally the handheld provides internal data-logging and a fully customizable gauge display
    Description_FAB The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up
    Description_FAB Plug and play compatible with multiple Holley EFI accessories including our gauges, shift lights, various modules, and digital and pro dashes (Holley P/N's 553-106, 553-111, and 553-112)
    Description_FAB Free EFI Tuning Software for complete control of your Terminator X power plant
    Description_FAB Includes: 58x/4x LS Engine Main Harness - EV6 Injector Harness - Terminator X ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters
    Description_INV TERMINATOR X MPFI, LS2/LS3 & LATE TRUCK
    Description_ASC Terminator X ECU's are designed to be mounted with the LED's facing up.
    Description_DES Holley EFI Terminator X - Gen IV 4.8/5.3/6.0 GM Truck Engines and LS2/LS3
    Description_EXT 58x Crank - 4x Cam - EV6 Injectors - 3.5 in. Touchscreen
    Description_MKT Take control of your LS engine with Terminator X. Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley EFI at a budget-friendly price.
    Description_MKT Terminator X features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Terminator X comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast. The 3.5" touch screen LCD handheld contains an easy to use calibration wizard as well as tuning and gauge display functions. Also included is Holley EFI's industry-leading, easy-to-use software suite that allows full laptop access for advanced users. Whether you are building a budget beater or a boosted race car, Terminator X has the features and technology you need at a price that won't break the bank.
    Description_FAB Designed for GM LS Engines with 58x Crank, 4x Cam - and EV6 Injectors
    Description_FAB Real-Time fuel map learn takes the guess work out of tuning your base fuel table
    Description_FAB High Impedance Injector Drivers will safely power most Stock LS injectors and Holley EFI Injectors; injector support chart provided in the instructions (will not control Low Impedance Injectors)
    Description_FAB All of the new Terminator X systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control
    Description_FAB MAP Sensor vacuum hose adapters (1/8th – ¼ and 3/16ths)
    Description_FAB 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, activation triggers for nitrous activation, or a trans brake
    Description_FAB 4 Outputs – Ground, PWM - for accessories such as fans, boost control, nitrous control, IAC Kit, and more
    Description_FAB Boost Control – Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
    Description_FAB Nitrous Control – Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
    Description_FAB On-Board Diagnostic LEDS for: ECU Power – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allows you to identify any Critical engine issues at a glance
    Description_FAB Advanced Tables – 4x 1D Tables, 1x 1D per Gear Table, 4x 2D Tables, 1x 2D per Gear Table can be used for any custom tables you can dream up, such as Flex Fuel Sensor Offset Table, or a custom fuel or oil pressure safety
    Description_FAB The included 3.5" Touchscreen Handheld contains a calibration wizard, that allows you to quickly build a base tune for any LS engine. Additionally the handheld provides internal data-logging and a fully customizable gauge display
    Description_FAB The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up
    Description_FAB Plug and play compatible with multiple Holley EFI accessories including our gauges, shift lights, various modules, and digital and pro dashes (Holley P/N's 553-106, 553-111, and 553-112)
    Description_FAB Free EFI Tuning Software for complete control of your Terminator X power plant
    Description_FAB Includes: 58x/4x LS Engine Main Harness - EV6 Injector Harness - Terminator X ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters


    Shipping Policy

    Shipping Policy Last Updated: April 2026

    We're committed to getting your order to you as quickly and transparently as possible. Here's everything you need to know about how we ship.

    Order Cancellations

    Once an order is placed, cancellations are not guaranteed as orders are sent to fulfillment quickly. If you need to cancel, contact us immediately at sales@berryperformancesales.com. If a cancellation is possible, the buyer is responsible for any transaction fees incurred. If the order has already shipped, it cannot be cancelled and must go through our standard return process.

    Processing Time

    In-stock orders are typically processed and shipped within 1–2 business days of receiving payment, unless otherwise noted on the product page. Orders placed on weekends or holidays will be processed on the next business day.

    Shipping Costs

    Shipping costs are calculated at checkout based on the shipping method selected, package weight and dimensions, and destination address. You can review all shipping costs before finalizing your purchase.

    Estimated Delivery Times

    Domestic orders typically arrive within 1–7 business days after shipment, depending on your location and the carrier. Please note that delivery times are estimates and are not guaranteed. Delays due to weather, carrier volume, or other circumstances beyond our control may occur.

    Tracking Information

    Once your order ships, you will receive a confirmation email with tracking information. Use this to monitor your package's progress. If your tracking has not updated within 48 hours of receiving your confirmation email, please contact us and we'll look into it.

    Shipping Address

    Please ensure your shipping address is accurate and complete before placing your order. If you realize an error after ordering, contact us immediately at sales@berryperformancesales.com — we will do our best to make the correction, but changes cannot be guaranteed once an order is in fulfillment. We are not responsible for orders shipped to incorrect or undeliverable addresses due to customer error.

    Please note: We are unable to ship to P.O. Boxes. Please provide a physical delivery address at checkout.

    Lost or Stolen Packages

    If your tracking shows your order as delivered but you have not received it, please take the following steps:

    • Check around your property and with neighbors
    • Confirm the shipping address on your order was correct
    • Contact the carrier directly with your tracking number

    If the issue remains unresolved, contact us at sales@berryperformancesales.com within 5 business days of the marked delivery date. We will work with you and the carrier to investigate. Berry Performance Sales is not responsible for packages confirmed as delivered by the carrier or for packages stolen after delivery.

    Damaged in Transit

    If your order arrives visibly damaged, please refer to our Returns & Refunds policy for instructions on how to report the issue. Carrier damage claims must be reported within 48 hours of delivery.

    International Shipping

    We do ship internationally! Because shipping costs, carrier options, and transit times vary significantly by destination, international orders require a custom quote prior to purchase. To request a shipping quote, contact us at sales@berryperformancesales.com with the following:

    • Your country and full delivery address
    • The item(s) you are interested in ordering

    We will respond with a shipping quote as quickly as possible. Please note that customs duties, import taxes, and any other fees charged upon delivery are the sole responsibility of the recipient and are not included in your shipping quote. We recommend checking with your local customs office before placing your order.

    Off-Road Use Disclaimer

    All products are sold for off-road use only unless otherwise specified. The buyer assumes full responsibility for installation and operation. Berry Performance Sales is not liable for any incidental, indirect, or consequential damages including engine failure, labor charges, or vehicle downtime resulting from the use of any product sold. By placing an order, you acknowledge and accept these terms.

    Questions?

    We're happy to help before, during, or after your purchase. Email: sales@berryperformancesales.com

    Berry Performance Sales reserves the right to update this policy at any time. Changes take effect immediately upon posting. It is the customer's responsibility to review the current policy at the time of purchase.

    Return Policy

    Returns & Refunds Last Updated: April 2026

    We want you to love what you ordered. If something isn't right, here's everything you need to know.

    30-Day Return Window

    You have 30 days from the date of purchase to initiate a return. After this window, we are unable to accept returns. We do not offer exchanges — all approved returns are refunded per the terms below.

    How to Initiate a Return

    To request a return, contact us at sales@berryperformancesales.com with your order number and reason for return. All returns must be approved by our team before any item is shipped back to us. Once your return has been approved, your item must be shipped within 10 days of approval. Items shipped without prior approval or outside this window will be refused and returned to sender.

    Return Conditions

    To be eligible for a return, items must be:

    • Unused and in original condition
    • In original packaging
    • Inclusive of all parts and accessories

    Custom ordered products are non-returnable. If you're unsure whether your item qualifies, contact us before purchasing.

    Once we receive your return, we will inspect the item before processing any refund. We reserve the right to deny or adjust your refund if the item is received in a condition that differs from what was originally shipped — including signs of use, missing parts, or damage that occurred after delivery.

    Fees to Know Upfront

    We believe in being transparent about costs:

    • Restocking Fee: 20% — deducted from all return refunds
    • Return Shipping: Buyer's responsibility on all standard returns
    • Cancellation (Installment/Payment Plan): 7% fee to cover transaction costs
    • Cancellation (Credit Card/PayPal): 3.5% processing fee

    Damaged or Defective Items

    If your order arrives damaged or defective, you must contact us within 48 hours of delivery at sales@berryperformancesales.com. Claims reported outside this window may not be eligible for resolution.

    When contacting us, please include:

    • Your order number
    • A description of the issue
    • Clear photos or video of the damage or defect

    If your item was damaged during shipping, this is handled as a carrier claim separate from our standard return process — we will assist you in filing that claim. Items confirmed to be defective due to a manufacturing or fulfillment error will have return shipping costs covered by Berry Performance Sales.

    Refunds

    Once we receive and inspect your return, refunds are processed within 3–5 business days back to your original payment method. You'll receive a confirmation once it's been issued.

    Questions?

    We're happy to help before, during, or after your purchase. Email: sales@berryperformancesales.com

    Berry Performance Sales reserves the right to update this policy at any time. Changes take effect immediately upon posting. It is the customer's responsibility to review the current policy at the time of purchase.

    Disclaimer

    All products are sold for off-road use only unless otherwise specified. Buyer assumes all responsibility for installation and operation. Seller is not liable for any incidental, indirect, or consequential damages — including engine failure, labor costs, or vehicle downtime — resulting from the use of any product sold.

    By making a purchase from Berry Performance Sales, you acknowledge and agree to abide by the terms and conditions of these Policies.

    For any questions or concerns, please contact us — we’re always happy to help.

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