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Holley EFI 550-903T Terminator X 24x/1x EV1 LS MPFI Kit - Without 3.5" Handheld
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Key item features
- Engine Compatibility: Designed for GM LS1/LS6 engines with 24x crank reluctor and EV1 injectors, supporting most stock LS and Holley EFI high impedance injectors.
- Advanced Tuning: Features real-time fuel map learning, an integrated Bosch LSU 4.9 wideband sensor for accurate AFR, and free EFI tuning software for comprehensive control.
- Integrated Sensors: Includes an on-board 1bar MAP sensor suitable for N/A or Nitrous setups, with vacuum hose adapters provided.
- Versatile Control: Offers 4 programmable inputs for various sensors or activation triggers, along with boost control and single-channel nitrous control capabilities.
- Diagnostic Aids: Equipped with on-board diagnostic LEDs for ECU power, engine run, wideband status, TPS calibration, and crank/cam signals.
- Compact Design: The ECU's compact size allows for flexible mounting, and it includes a CAN/USB tuning cable for real-time configuration.
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Specs
- Compatible carsLS1,LS6
- Vehicle makeGM
- Vehicle modelLS1, LS6
- BrandHOLLEY EFI
- Automotive parts divisionPerformance
- Vehicle fitment typeSpecific
Current price is USDNow $1,258.95
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was $1,359.95$1,359.95
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Columbus, 43215
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| Product | Viewing this itemHolley EFI 550-903T Terminator X 24x/1x EV1 LS MPFI Kit - Without 3.5" Handheld ![]() Now $1,258.95 current price Now $1,258.95, Was $1,359.95$1,359.95 | Holley EFI 550-904T Terminator X 24x/1x Multec 2 LS MPFI Kit - Without 3.5" Handheld ![]() $1,258.95 current price $1,258.95 | Holley EFI 558-508 Fuel Injection Harness ![]() $805.95 current price $805.95 | Holley EFI 558-101 Fuel Injection Harness ![]() $649.95 current price $649.95 | Holley Performance 12-160 Electric Fuel Pump ![]() $89.60 current price $89.60 |
|---|
| Compatible cars | LS1,LS6Holley EFI 550-903T Terminator X 24x/1x EV1 LS MPFI Kit - Without 3.5" Handheld | 4.8,5.3,6.0 TRUCK ENGINESHolley EFI 550-904T Terminator X 24x/1x Multec 2 LS MPFI Kit - Without 3.5" Handheld | Ford V8Holley EFI 558-508 Fuel Injection Harness | Avenger EFIHolley EFI 558-101 Fuel Injection Harness | -Holley Performance 12-160 Electric Fuel Pump |
|---|---|---|---|---|---|
| Vehicle make | GMHolley EFI 550-903T Terminator X 24x/1x EV1 LS MPFI Kit - Without 3.5" Handheld | GMHolley EFI 550-904T Terminator X 24x/1x Multec 2 LS MPFI Kit - Without 3.5" Handheld | FordHolley EFI 558-508 Fuel Injection Harness | -Holley EFI 558-101 Fuel Injection Harness | -Holley Performance 12-160 Electric Fuel Pump |
| Vehicle model | LS1Holley EFI 550-903T Terminator X 24x/1x EV1 LS MPFI Kit - Without 3.5" Handheld | LSHolley EFI 550-904T Terminator X 24x/1x Multec 2 LS MPFI Kit - Without 3.5" Handheld | V8Holley EFI 558-508 Fuel Injection Harness | 558-101Holley EFI 558-101 Fuel Injection Harness | 12-160Holley Performance 12-160 Electric Fuel Pump |
| Automotive parts division | PerformanceHolley EFI 550-903T Terminator X 24x/1x EV1 LS MPFI Kit - Without 3.5" Handheld | PerformanceHolley EFI 550-904T Terminator X 24x/1x Multec 2 LS MPFI Kit - Without 3.5" Handheld | PerformanceHolley EFI 558-508 Fuel Injection Harness | PerformanceHolley EFI 558-101 Fuel Injection Harness | PerformanceHolley Performance 12-160 Electric Fuel Pump |
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About this item
Product details
GM LS 24x Crank, 1x Cam - LS1/LS6 Engines - EV1 Injector Harness, USB/CAN Tuning Cable;
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 NOS 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. These Terminator X kits include a USB/CAN tuning cable instead of the 3.5 in. Handheld LCD, these kits require the use of the free Terminator X Software for initial setup. The Terminator X Software includes multiple base calibrations to choose from for either naturally aspirated or boosted engines. 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!;
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 NOS 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. These Terminator X kits include a USB/CAN tuning cable instead of the 3.5 in. Handheld LCD, these kits require the use of the free Terminator X Software for initial setup. The Terminator X Software includes multiple base calibrations to choose from for either naturally aspirated or boosted engines. 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!;
- 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 â€" Â1/4 and 3/16ths)
- 4 Inputs â€" 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
- Boost Control â€" Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
- Nitrous Control â€" Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
- Advanced Tables â€" 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 â€" Engine Run â€" Wideband Status â€" TPS Calibration â€" Crank Signal â€"Cam Signal. Allow you to identify any Critical engine issues at a glance
- Includes CAN/USB tuning cable allowing you to configure your ECU and Tuning the engine in real time.
- The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up!
- Plug and play compatible with more Holley EFI accessories such as; analog style gauges, shift lights, various modules, and coming soon, 12.3" digital dash support!
- 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.
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Specifications
Compatible cars
LS1,LS6
Vehicle make
GM
Vehicle model
LS1, LS6
Fuel injection accessory & part type
EV1 Injector Harness, USB/CAN Tuning Cable
Warranty
Warranty information
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Please be aware that the warranty terms on items offered for sale by third party Marketplace sellers may differ from those displayed in this section (if any). To confirm warranty terms on an item offered for sale by a third party Marketplace seller, please use the 'Contact seller' feature on the third party Marketplace seller's information page and request the item's warranty terms prior to purchase.
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Warnings
Warning Text
California Proposition 65
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