{"product_id":"holley-efi-terminator-x-max-for-gen-iv-gm-ls-engines-58x-4x-ev6-4l60e-4l80e-control","title":"Holley EFI Terminator X Max for Gen IV GM LS Engines – 58x\/4x, EV6, 4L60E\/4L80E Control","description":"\u003cp\u003eThe \u003cstrong\u003eHolley EFI Terminator X Max for Gen IV GM LS Engines – 58x\/4x, EV6, 4L60E\/4L80E Control\u003c\/strong\u003e gives builders complete control over compatible GM LS truck engines, LS2, and LS3 combinations without relying on a modified factory ECU. This system combines self-learning fuel control, ignition timing control, wideband oxygen sensing, programmable inputs and outputs, data logging, and electronic transmission control in one compact package.\u003c\/p\u003e\n\u003cp\u003eDesigned for Gen IV LS engines using a 58x crank reluctor, 4x cam signal, USCAR\/EV6 injectors, and cable-operated throttle bodies, the Terminator X Max supports 4L60E and 4L80E electronic transmissions. \u003cstrong\u003eChoose PN 550-918 with the 3.5\" touchscreen handheld \u003c\/strong\u003eor \u003cstrong\u003ePN 550-918T without the handheld\u003c\/strong\u003e for installations using a laptop or compatible Holley display.\u003c\/p\u003e\n\u003ch4\u003eIncludes:\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e(1) Holley Terminator X Max ECU\u003c\/li\u003e\n\u003cli\u003e58x\/4x GM LS Engine Main Harness\u003c\/li\u003e\n\u003cli\u003eUSCAR\/EV6 Injector Harness\u003c\/li\u003e\n\u003cli\u003e4L60E\/4L80E Transmission Control Harness\u003c\/li\u003e\n\u003cli\u003eECU Main Power Harness\u003c\/li\u003e\n\u003cli\u003eBosch LSU 4.9 Wideband Oxygen Sensor\u003c\/li\u003e\n\u003cli\u003eInput\/Output Harness\u003c\/li\u003e\n\u003cli\u003eMAP Sensor Vacuum Hose Adapters\u003c\/li\u003e\n\u003cli\u003e3.5\" Touchscreen Handheld with PN 550-918 Only\u003c\/li\u003e\n\u003cli\u003eFuel System Components, Injectors, Throttle Body, and Mounting Hardware Not Included\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003cdetails class=\"details\"\u003e\n\u003csummary\u003e\u003cstrong\u003eSpecifications\u003c\/strong\u003e\u003cspan class=\"svg-wrapper icon-plus\"\u003e\u003csvg width=\"14\" height=\"14\" viewbox=\"0 0 14 14\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath class=\"vertical\" d=\"M2.75 7H11.25\" stroke=\"currentColor\" stroke-width=\"var(--icon-stroke-width)\" stroke-linecap=\"round\"\u003e\u003c\/path\u003e\u003cpath class=\"horizontal\" d=\"M7 2.75L7 11.25\" stroke=\"currentColor\" stroke-width=\"var(--icon-stroke-width)\" stroke-linecap=\"round\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\u003c\/span\u003e\u003c\/summary\u003e\n\u003cdiv class=\"details-content rte\"\u003e\n\u003ctable class=\"custom-specs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eDetails\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer\u003c\/td\u003e\n\u003ctd\u003eHolley EFI\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Numbers\u003c\/td\u003e\n\u003ctd\u003e550-918 With Handheld \/ 550-918T Without Handheld\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eSelf-Tuning EFI and Transmission Control System\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEngine Family\u003c\/td\u003e\n\u003ctd\u003eGen IV GM LS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCrank Reluctor\u003c\/td\u003e\n\u003ctd\u003e58x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCam Signal\u003c\/td\u003e\n\u003ctd\u003e4x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIgnition Type\u003c\/td\u003e\n\u003ctd\u003eGM LS 58x Coil-Per-Cylinder\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInjector Connector\u003c\/td\u003e\n\u003ctd\u003eUSCAR \/ EV6\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInjector Driver Type\u003c\/td\u003e\n\u003ctd\u003eHigh Impedance\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Control\u003c\/td\u003e\n\u003ctd\u003e4L60E \/ 4L80E\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDrive-By-Wire Support\u003c\/td\u003e\n\u003ctd\u003eNo\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWideband Oxygen Sensor\u003c\/td\u003e\n\u003ctd\u003eBosch LSU 4.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInternal MAP Sensor\u003c\/td\u003e\n\u003ctd\u003e1 Bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProgrammable Inputs\u003c\/td\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProgrammable Outputs\u003c\/td\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBoost Control\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNitrous Control\u003c\/td\u003e\n\u003ctd\u003eWet or Dry, Progressive or Non-Progressive\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eE85 Support\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eData Logging\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCAN-BUS Support\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinish\u003c\/td\u003e\n\u003ctd\u003eBlack Textured\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003chr\u003e\n\u003cdetails class=\"details\"\u003e\n\u003csummary\u003e\u003cstrong\u003eFitment\u003c\/strong\u003e\u003cspan class=\"svg-wrapper icon-plus\"\u003e\u003csvg width=\"14\" height=\"14\" viewbox=\"0 0 14 14\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath class=\"vertical\" d=\"M2.75 7H11.25\" stroke=\"currentColor\" stroke-width=\"var(--icon-stroke-width)\" stroke-linecap=\"round\"\u003e\u003c\/path\u003e\u003cpath class=\"horizontal\" d=\"M7 2.75L7 11.25\" stroke=\"currentColor\" stroke-width=\"var(--icon-stroke-width)\" stroke-linecap=\"round\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\u003c\/span\u003e\u003c\/summary\u003e\n\u003cdiv class=\"details-content rte\"\u003e\n\u003ctable class=\"custom-specs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eEngine Application\u003c\/th\u003e\n\u003cth\u003eCompatibility\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e294 \/ 4.8L V8\u003c\/td\u003e\n\u003ctd\u003eCompatible with 58x Crank, 4x Cam, and EV6 Injectors\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e325 \/ 5.3L V8\u003c\/td\u003e\n\u003ctd\u003eCompatible with 58x Crank, 4x Cam, and EV6 Injectors\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e346 \/ 5.7L V8\u003c\/td\u003e\n\u003ctd\u003eCompatible with 58x Crank, 4x Cam, and EV6 Injectors\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e364 \/ 6.0L V8\u003c\/td\u003e\n\u003ctd\u003eCompatible with 58x Crank, 4x Cam, and EV6 Injectors\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e376 \/ 6.2L V8\u003c\/td\u003e\n\u003ctd\u003eCompatible with LS2\/LS3-Based 58x\/4x Applications\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e427 \/ 7.0L V8\u003c\/td\u003e\n\u003ctd\u003eCompatible with Proper 58x\/4x and EV6 Configuration\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eElectronic Transmission\u003c\/td\u003e\n\u003ctd\u003e4L60E or 4L80E\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThrottle Control\u003c\/td\u003e\n\u003ctd\u003eCable-Operated Throttle Body\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFitment Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDesigned for Gen IV GM LS engines with a 58x crank reluctor and 4x cam signal.\u003c\/li\u003e\n\u003cli\u003eRequires high-impedance injectors with USCAR\/EV6 connectors.\u003c\/li\u003e\n\u003cli\u003eWill not control low-impedance fuel injectors.\u003c\/li\u003e\n\u003cli\u003eDesigned for cable-operated throttle bodies and does not support drive-by-wire throttle control.\u003c\/li\u003e\n\u003cli\u003eTransmission control is provided for compatible 4L60E and 4L80E transmissions.\u003c\/li\u003e\n\u003cli\u003eNot compatible with 4L6X transmissions from model year 1995 or earlier due to converter lockup and downshift strategy differences.\u003c\/li\u003e\n\u003cli\u003eNot recommended for four-wheel-drive applications using an electronically controlled transfer case.\u003c\/li\u003e\n\u003cli\u003eThe internal 1-bar MAP sensor is intended for naturally aspirated or nitrous combinations.\u003c\/li\u003e\n\u003cli\u003eBoosted applications requiring a 2-bar or higher MAP sensor can use GM PN 12592525 with Holley adapter PN 558-416.\u003c\/li\u003e\n\u003cli\u003eThe ECU is not recommended for marine use.\u003c\/li\u003e\n\u003cli\u003eOff-road installations must keep the ECU dry, protected from heat, and mounted with the diagnostic LEDs facing upward.\u003c\/li\u003e\n\u003cli\u003eVerify crank reluctor, cam signal, injector connector, throttle type, and transmission compatibility before ordering.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003chr\u003e\n\u003cdetails class=\"details\"\u003e\n\u003csummary\u003e\u003cstrong\u003eFAQ\u003c\/strong\u003e\u003cspan class=\"svg-wrapper icon-plus\"\u003e\u003csvg width=\"14\" height=\"14\" viewbox=\"0 0 14 14\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath class=\"vertical\" d=\"M2.75 7H11.25\" stroke=\"currentColor\" stroke-width=\"var(--icon-stroke-width)\" stroke-linecap=\"round\"\u003e\u003c\/path\u003e\u003cpath class=\"horizontal\" d=\"M7 2.75L7 11.25\" stroke=\"currentColor\" stroke-width=\"var(--icon-stroke-width)\" stroke-linecap=\"round\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\u003c\/span\u003e\u003c\/summary\u003e\n\u003cdiv class=\"details-content rte\"\u003e\n\u003ch3\u003e1. What is the difference between PN 550-918 and PN 550-918T?\u003c\/h3\u003e\n\u003cp\u003ePN 550-918 includes the 3.5\" touchscreen handheld, while PN 550-918T does not. Both versions include the Terminator X Max ECU, engine harness, transmission harness, wideband oxygen sensor, power harness, and supporting EFI wiring.\u003c\/p\u003e\n\u003ch3\u003e2. What does the self-learning feature do?\u003c\/h3\u003e\n\u003cp\u003eThe ECU monitors air-fuel ratio through the Bosch LSU 4.9 wideband sensor and makes real-time corrections to the base fuel table. This helps establish a usable tune faster, but the installation still requires proper engine setup, sensor configuration, and verification.\u003c\/p\u003e\n\u003ch3\u003e3. Can this system control a 4L60E or 4L80E transmission?\u003c\/h3\u003e\n\u003cp\u003eYes. The Terminator X Max includes electronic control for compatible 4L60E and 4L80E transmissions, allowing transmission functions to be configured through the Holley EFI software or handheld interface.\u003c\/p\u003e\n\u003ch3\u003e4. Can the Terminator X Max control a boosted or nitrous engine?\u003c\/h3\u003e\n\u003cp\u003eYes. The ECU supports boost control, wet or dry nitrous, progressive nitrous control, boost and nitrous safeties, and advanced custom tables. Boosted combinations require a properly sized external MAP sensor because the internal sensor is limited to 1 bar.\u003c\/p\u003e\n\u003ch3\u003e5. What can the four inputs and four outputs be used for?\u003c\/h3\u003e\n\u003cp\u003eThe programmable inputs can monitor switches, pressure sensors, nitrous activation, trans brake signals, and other triggers. The outputs can control relays and devices such as electric fans, boost solenoids, nitrous systems, warning lights, and compatible idle air control hardware.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003chr\u003e","brand":"Holley","offers":[{"title":"With Handheld","offer_id":56886391406758,"sku":"550-918","price":1999.95,"currency_code":"USD","in_stock":true},{"title":"No Handheld","offer_id":56886391439526,"sku":"550-918T","price":1949.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0693\/8394\/6406\/files\/550-918-Holley-TerminatorX-Max-GM-LS-ECU-1.jpg?v=1785441404","url":"https:\/\/wideopendesign.com\/products\/holley-efi-terminator-x-max-for-gen-iv-gm-ls-engines-58x-4x-ev6-4l60e-4l80e-control","provider":"Wide Open Design","version":"1.0","type":"link"}