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    Sale!

    Holley Terminator X Max, Universal V8, DBW, EV1 | 550-950

    Vendor: Holley EFI
    Part Number: 550-950
    Save $250
    Sale Price $1,999.95 Regular Price $2,249.95

    In 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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    Terminator X Max is a self-learning Holley EFI engine management kit for domestic V8 engines, such as conventional pushrod Chevrolet and Chrysler engines. It replaces a factory or junkyard controller with real-time fuel learn, high-impedance injector drivers and Holley EFI tuning software. This version is configured for an EV1 injector harness and drive-by-wire throttle body control. A 3.5 in. touchscreen handheld with a calibration wizard is included for setup, tuning and gauge display.

    Key Features:

    • Built for domestic V8 engines, such as conventional pushrod Chevrolet and Chrysler engines
    • Real-time fuel map learning builds and refines the base fuel table
    • High-impedance injector drivers run most stock injectors and Holley EFI injectors; low-impedance injectors are not supported
    • Bosch LSU 4.9 wideband oxygen sensor control for accurate AFR readings and closed-loop tuning
    • Built-in 1-bar MAP sensor suited to naturally aspirated or nitrous combinations
    • For boosted use, the internal MAP sensor can be disabled and an external MAP sensor connected to the pre-terminated harness connector
    • 4 programmable inputs (12V, ground, 5V, frequency) and 4 outputs (ground, PWM) for sensors, fans, boost and nitrous control, IAC kits and more
    • Boost control by time, gear, RPM or speed, with boost safeties
    • Single-channel wet or dry nitrous control, progressive or non-progressive, with rich/lean safeties and closed-loop AFR target
    • Advanced 1D and 2D custom tables, including per-gear tables, for uses such as a flex fuel offset or a fuel or oil pressure safety
    • On-board diagnostic LEDs for ECU power, engine run, wideband status, TPS calibration, crank signal and cam signal
    • 3.5 in. touchscreen handheld with calibration wizard, internal data logging and customizable gauge display
    • Plug-and-play ignition capability with Holley Dual Sync and HyperSpark distributors (HyperSpark requires adapter 558-323)
    • Compact ECU can be mounted almost anywhere, with the diagnostic LEDs facing up
    • Plug-and-play with Holley EFI gauges, shift lights, modules and digital/pro dashes (P/N 553-106, 553-111, 553-112)
    • Free Holley EFI tuning software provides full laptop access for advanced users
    • Recommended GM throttle pedal: P/N 10379038

    Specifications:

    • Engine: Universal domestic V8 (MPFI)
    • Injector Connector: Jetronic/Minitimer (Bosch EV1)
    • Throttle Control: Drive-by-wire (DBW)
    • Transmission Control: None
    • MAP Sensor: 1-bar, internal
    • Handheld Included: Yes, 3.5 in. touchscreen
    • Part Number: 550-950

    Designed to work with GM throttle body P/N 12570790 and 12580760 and GM throttle pedal P/N 10379038. Not recommended for marine use; it can be used off-road when mounted in a safe, dry location protected from heat with proper wiring management. Mount the ECU with the LEDs facing up.

    FAQ

    What engines does the 550-950 fit?

    It is built for domestic V8 engines, such as conventional pushrod Chevrolet and Chrysler engines.

    Is a handheld display included?

    Yes. A 3.5 in. touchscreen handheld with a calibration wizard is included for setup, tuning and gauge display.

    Does it control the throttle body and transmission?

    It provides drive-by-wire throttle body control. It does not include transmission control.

    What fuel injector connector does the kit use?

    The injector harness uses the Jetronic/Minitimer (Bosch EV1) connector.

    Which throttle pedal is recommended?

    Holley recommends GM throttle pedal P/N 10379038 for drive-by-wire setups.

    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.

    Read the full Shipping Policy

    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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