Take control of an LS engine with Terminator X Max, a self-learning standalone EFI system that delivers Holley EFI's proven, race-winning technology at a budget-friendly price. Real-time fuel learn, high-impedance injector drivers, an integrated 1-bar MAP sensor, and four programmable inputs and outputs make it easy to add electric fans, boost control, progressive nitrous, and more. This kit adds 4L60E/4L80E transmission control and drive-by-wire throttle body control, and it comes fully loaded with base maps for common LS combinations. It ships with a USB/CAN tuning cable instead of a handheld, and requires the free Terminator X Software for setup.
Key Features:
- Designed for GM LS 4.8/5.3/6.0 truck engines and LS2/LS3 with 58x crank, 4x cam, and 4L60E/4L80E transmissions
- Drive-by-wire throttle body control and EV6 injector compatibility
- Real-time fuel map learn takes the guesswork out of tuning the base fuel table
- High-impedance injector drivers safely power most stock LS injectors and Holley EFI injectors
- Onboard Bosch LSU 4.9 wideband O2 sensor for accurate AFR reading and precise tuning
- Onboard 1-bar MAP sensor, ideal for N/A or nitrous combinations (2+ bar MAP requires GM 12592525 and adapter 558-416)
- Includes MAP sensor vacuum hose adapters (1/8", 1/4", 3/16")
- 4 inputs (12V, ground, 5V, frequency) for extra sensors or activation triggers
- 4 outputs (ground, PWM-) for fans, boost control, nitrous control, IAC kit, and more
- Boost control: boost vs. time, gear, RPM, speed, plus boost safeties
- Nitrous control: single channel wet or dry, progressive or non-progressive, with rich/lean safeties
- Advanced tables: 4x 1D tables, 1x 1D-per-gear table, 4x 2D tables, 1x 2D-per-gear table for custom uses like flex fuel offset or fuel/oil pressure safeties
- Onboard diagnostic LEDs for ECU power, engine run, wideband status, TPS calibration, crank signal, and cam signal
- Includes USB/CAN tuning cable for real-time configuration and tuning
- Compact ECU mounts virtually anywhere
- Plug-and-play compatible with Holley EFI gauges, shift lights, and digital/pro dashes (553-106, 553-111, 553-112)
Specifications:
- Engine: Gen IV GM LS 4.8/5.3/6.0 Truck, LS2/LS3
- Crank Reluctor: 58x
- Ignition Type: GM LS 58x
- Injector Connector: USCAR (EV6)
- Drive-By-Wire: Yes
- Transmission Control: 4L60E/4L80E
- MAP Sensor: 1-Bar (onboard)
- Performance Handheld Included: No (USB/CAN tuning cable included instead)
- Control Options: Fuel, Spark, Drive-by-Wire, Transmission
- Includes: 58x/4x LS main harness, EV6 injector harness, DBW throttle body harness, 4L60E/4L80E transmission control harness, Terminator X MAX ECU, ECU main power harness, Bosch LSU 4.9 wideband oxygen sensor, I/O harness
- Part Number: 550-928T
Not recommended for 4x4 applications with electronic transfer cases, and not compatible with 4L6X transmissions from model year 1995 or earlier due to year-by-year converter lockup and downshift strategy changes. The ECU is not recommended for marine use, but can be used in off-road applications if mounted in a safe, dry, heat-protected location with proper wiring management.
FAQ
What engines is Terminator X Max 550-928T designed for?
It's built for Gen IV GM LS 4.8/5.3/6.0 truck engines and LS2/LS3 engines with a 58x crank and 4x cam.
Does this kit control the transmission and throttle body?
Yes, this kit includes 4L60E/4L80E transmission control and drive-by-wire throttle body control.
Does it come with a handheld tuner?
No, this kit includes a USB/CAN tuning cable instead of the 3.5" handheld, and requires the free Terminator X Software for setup.
What MAP sensor does it use?
It has an onboard 1-bar MAP sensor, suited to naturally aspirated or nitrous combinations; boosted applications above 1 bar require a separate 2+ bar sensor and adapter.
Is this ECU suitable for 4x4 trucks?
It's not recommended for 4x4 applications with electronic transfer cases.
Can this ECU be used in a marine or off-road application?
It's not recommended for marine use, but can be used off-road if mounted in a safe, dry, heat-protected location with proper wiring management.