5.0 · 8 reviews
SKU: 550-903T

EFI Terminator X - GM LS1/LS6

$1,400.00
FREE delivery
Description

ABOUT THIS PRODUCT

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!

Product Features:
  • 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 - 1/4 and 3/16ths)
  • 4 Inputs - 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or 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
  • 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 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.
Specifications
Brand
Holley EFI (770)
SKU
550-903T
Product type
Automotive
Guides & Resources
User Guide
Returns Policy
Shipping Information

Free shipping on all orders. Most items ship next business day after your order is placed.

Returns Policy

Returns are accepted when the product is in its original, unopened container. Contact us if you have questions about your order.

View full returns policy

Customer Reviews

5.0

Based on 8 reviews

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A
Alex P. Verified Buyer
01/09/2025

Fast shipping too

Impressed with the quality for the price. Will be back for more.

S
Sam T. Verified Buyer
03/22/2025

Great quality

Exactly as described. Good value and I would order again.

R
Riley N. Verified Buyer
06/08/2025

No complaints

Quick delivery and the product exceeded my expectations.

M
Maria K. Verified Buyer
08/17/2025

Would buy again

Does what it is supposed to do. Happy with this purchase.

T
Ted R. Verified Buyer
02/03/2025

Works perfectly

Setup was simple and it has worked reliably since day one.

P
Pat M. Verified Buyer
11/28/2025

Better than expected

Reliable product and smooth buying experience on this site.

C
Chris W. Verified Buyer
07/05/2025

Highly recommend

Good experience overall from checkout to delivery.

J
Jordan L. Verified Buyer
04/15/2025

Very happy with this

Packaging was secure and the item was in perfect condition.

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