-10% Terminator X MPFI Kit for Dodge Gen 3 Hemi Engine

What's Terminator X?

Holley's Terminator X family of EFI Systems are standalone engine management systems that closely replicate some of Holley's most advanced engine management systems but at a much more budget-friendly price. This PDF gives a highly detailed comparison of the Terminator X to engines built using the Holley HP and Dominator ECUs. To summarize, Holley was able to leave out some features found to be less-necessary by the majority of users and, in doing do, slash the price of a full-featured EFI System by half.  If you're switching your carbureted engine to multi-point EFI or are swapping a fuel-injected engine into your ride and need to stay on a budget, this is the EFI system for you.

Here are some of the features that are included in each Terminator X kit:

Different Terminator X EFI Systems For Different Applications

Yes, there are quite a few different Terminator X EFI System--nearly 100 with more on the way.  All Terminator X systems include the Terminator X ECU. This ECU includes an on-board 1-BAR MAP sensor or you can add an external MAP sensor for boosted applications. On-Board Diagnostic LEDs display the status of ECU Power, Engine Run, Wideband Status, TPS Calibration, Crank Signal, and Cam Signal

In addition to the ECU the kit all Terminator X systems include the following:

  • ECU Power Harness
  • Application-Specific Main Harness
  • 3.5-inch Touchscreen LCD Display with Setup Wizard app
  • Custom 4-input / 4-output harness pre-configured for two Electric Fans, A/C Kick, and A/C Shutdown
  • Bosch LSU 4.9 Wideband O2 Sensor

Unique To The Terminator X MPFI Kit for Dodge Gen 3 Hemi Engine

Holley provides many features unique to the Dodge Gen 3 Hemi Engine that make this EFI system a breeze to install and configure and powerful to operate.

  • Direct-fit connectors for factory sensors
  • Ignition harness for factory ignition coils
  • Two Four-Channel Coil Driver Modules for factory Ignition Coils
  • Choose from EV1 or EV6 injector harness

Choose From Four Different Versions of the Terminator X MPFI Kit for Dodge Gen 3 Hemi Engine

Part NumberManuf.EngineECUInjector
550-1222DodgeGen3 Hemi Engine 03-06XEV1NoNo
550-1223DodgeGen3 Hemi Engine 03-06XEV6NoNo
550-1224DodgeGen3 Hemi Engine 07-13+XEV1NoNo
550-1225DodgeGen3 Hemi Engine 07-13+XEV6NoNo
550-1420DodgeGen3 Hemi Engine 03-06X MaxEV1NoYes
550-1421DodgeGen3 Hemi Engine 03-06X MaxEV6NoYes
550-1422DodgeGen3 Hemi Engine 07-12X MaxEV1NoYes
550-1423DodgeGen3 Hemi Engine 07-12X MaxEV6NoYes
550-1424DodgeGen3 Hemi Engine 13+X MaxEV1NoYes
550-1425DodgeGen3 Hemi Engine 13+X MaxEV6NoYes

But Wait--There's More!

No, we're not going to send you a set of Ginsu knives with your Terminator X for Gen III Hemi. But if you have an '09 or later Gen III Hemi you definitely need to add VVT Control. There are two harness options for this: The 558-131 VVT Harness (for aftermarket intake manifolds) or the 558-132 VVT and SRV harness (for factory manifolds that feature the Short Runner Valve) for impressive low-RPM torque gains. For more information, including product video, or to order ala carte, check out this Gen III Hemi VVT Harness Product Page.

Or maybe you have the Chyrsler 46RE electroic transmission ('96-'03) and need a controller. Then you will absolutely want to opt for the Terminator X-Max and add the 558-473 Chrysler 46RE Transmission Control Harness. Why outsource this to an external controller when you can put fuel injection, ignition, transmission control, and more into the same system?  Note that to use this you will have to opt for one of the 550-1420 through 550-1425 systems that include the Terminator X-Max ECU (does not work on the standard Terminator X ECU, PNs 550-1222 through 550-1225.) For more information, or to order ala carte, check out this 46RE Transmission Harness Product Page.

What Else Will I Need?

Required:  EFI Fuel System with

  • EFI Fuel Pump (Many great options here)
  • Pre- and Post-Pump Filters
  • Fuel Pressure Regulator
  • Associated Hose, Hose Ends, Clamps, Adapters, Etc.


Important Note about Coil Harnesses in 2006

Dodge changed the coils they used in the middle of the 2006 production year. Holley ships the early coil harness (558-310) in their Terminator X kits for the 03-06 Hemi but if you have a Hemi engine that was built in 2006 there is a chance you need the late coil harness (558-311).  Fortunately, this is easy to determine. Look at the image in the gallery above that compares the early and late coils. If you have an '06 and need the late coil harness simply let us know when ordering and we'll make the swap on our end before shipping. This will avoid delays later that will require the return of the early coil harness and the shipping of the late one.

Not Sure? Review this product documentation before you buy!

Quickstart Manual
Holley Terminator X and X Max EFI Systems

Tuning Manual
Holley Terminator X and X Max EFI Systems

Installation Guide
Holley Gen III HEMI Main Harness
(For use with for Holley Throttle Body)

Boost ControlYes (Requires Additional Hardware)
DIS OutputsEight
FamilyTerminator X
Fueling StrategySpeed Density, Alpha-N, or Combination
Includes Power HarnessYes
Injector DriversEight High Impedance
Internal DataloggingNo. All datalogging done via external device (handheld, laptop, digital display.)
Nitrous ControlYes (Requires Additional Hardware)
Number of CylindersEight
User Configurable I/OYes
User-Selectable MAP StorageNo
Water-Methanol ControlNo
Displays And Controllers
Auto BrightnessNo
CAN Bus CapableYes (Specific to Holley ECUs Only)
Case/Bezel FinishBlack
ConfigurableMonitor dozens of pre-configured metrics provided by the ECU, including sensors, air/fuel ratio, switched outputs, and more.
Data LoggingYes
Display TypeLCD
FunctionsSetup, Monitor, Tuning
Gauge/Display Size3.5 Inch Rectangular
Internal StorageYes (SD Card)
Harness TypePower Harness, Main Harness, Injector Sub-Harness, I/O Harness, Ignition Adapter, DBW Harness (DBW Versions Only)
Crank Timing
Sensor Harness IncludedDirect-Fit Connector to Factory Crank Timing Pickup
TypeECU-mounted 1 BAR MAP, Wideband O2
Also IncludedI/O Harness
ApplicationDodge Gen 3 Hemi Engine 03-06 or Dodge Gen 3 Hemi Engine 07-13+
Emission Code3 - This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles and Racing Use Only Vehicles.
Unit of SaleKit

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Terminator X MPFI Kit for Dodge Gen 3 Hemi Engine

  • Views: 25909
  • Brand: Holley EFI
  • Product Code: 550-1222 - 550-1225 & 550-1420 - 550-1425
  • Availability: In Stock
  • $2,033.00
  • $1,828.95

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