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    New!

    Holley EFI Holley EFI Terminator X - GM LS1/LS6 550-903-2

    Vendor: Holley EFI
    Part Number: 550-903-2
    Save $400
    Sale Price $3,198.95 Regular Price $3,598.95

    Currently out of stock.

    Not sure it fits your vehicle?
    Email sales@berryperformancesales.com with your year, make, model and engine, and we'll help you check fitment before you order.
    Fast Fulfillment: In-stock orders typically ship within 1 to 2 business days.
    Free Shipping on Orders Over $99 | Excludes freight shipments
    International Shipping Available: email sales@berryperformancesales.com for a quote.
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    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. 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 V8 engine combinations to get you out of the garage and on the road/track fast.


    Holley EFI Holley EFI Terminator X - GM LS1/LS6 550-903-2


    Specifications:

    10429 Yes
    10431 Yes
    Brand Holley EFI
    10423 Yes
    Category Air and Fuel Delivery
    10438 Yes
    Color Black
    Crank Reluctor 24x
    10430 Yes
    10437 No
    Drive-By-Wire No
    10442 Yes
    10418 Yes
    10428 Yes
    Emission Code 3
    Engine GM LS1/LS2/LS6
    Finish Textured
    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 24x
    10432 Yes
    Injector Connector Jetronic/Minitimer (Bosch EV1)
    9780 No
    10427 Yes
    MAP Sensor 1bar
    30 No
    10420 Yes
    part type Fuel Injection System
    Product Type EFI System
    10421 Yes
    10434 Yes
    Sub Category Fuel Injection System and Related Components
    Terminator LS Options Fuel, Spark
    918 No
    Transmission None
    10435 Yes
    Warning California Proposition 65
    10419 Yes
    Display 12.3 in. Pro Dash w/ Bluetooth Module
    Description_ABR SNEFI FIS
    Description_SHO Terminator X - GM
    Description_INV TERMINATOR X MPFI LS1
    Description_ASC Terminator X ECU's are designed to be mounted with the LED's facing up.
    Description_DES Holley EFI Terminator X - GM LS1/LS6
    Description_EXT 24x Crank - 1x Cam - EV1 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. 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 V8 engine combinations to get you out of the garage and on the road/track fast.
    Description_FAB For GM LS1/LS6 engines with 24x crank reluctor - with EV1 Injectors Real-Time fuel map learn takes the guess work out of tuning your base fuel table 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) 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 On-Board 1bar MAP sensor, is perfect for N/A or Nitrous engine combos. If your combination requires a 2+Bar, we recommend GM 12592525 and our adapter part number 558-416 MAP Sensor vacuum hose adapters (1/8th – ¼ and 3/16ths) 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, activation triggers for nitrous activation, or a trans brake Boost Control – Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties Nitrous Control – Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR 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 On-Board Diagnostic LEDS for: ECU Power – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allow you to identify any critical engine issues at a glance 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 The compact ECU size allows you to mount it virtually anywhere, emember, diagnostic LEDS must face up 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) Free EFI Tuning Software for complete control of your Terminator X power plant Includes: 24x LS Engine Main Harness - EV1 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
    • Free shipping on orders over $99 (excludes freight shipments).
    • In-stock orders typically ship within 1 to 2 business days. Weekend and holiday orders are processed the next business day.
    • Orders ship from Defiance, Ohio and a nationwide network of warehouses and manufacturers.
    • Items showing an ETA are not in stock yet. ETAs come from the manufacturer and can change.
    • No P.O. Boxes. International orders need a shipping quote, so email us first.

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    Return Policy
    • 30-day return window from the ship date. Returns must be approved first; email sales@berryperformancesales.com with your order number.
    • Items must be unused, complete and in the original packaging.
    • A 20% restocking fee applies, and return shipping is paid by the buyer.
    • Not returnable: installed or modified parts, opened or used programmers and tuners, custom orders, Open Box, and Clearance or Final Sale items.
    • Damaged, defective or incorrect items must be reported within 48 hours of delivery with photos.

    Read the full Return Policy

    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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