Link G4+ Plug-In ECU for Subaru Impreza WRX & STI V7-9

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  • Regular price £1,392.00

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The Link G4+ range of engine management systems are already well known for delivering class-leading performance without sacrificing factory levels of drivability.


The G4+ plug-in ECUs are designed to be the most complete plug-in solution yet.


This V7-9 WRX/STI plug-in ECU will save you time and money as it will plug straight into the vehicle’s original wiring loom without the need for messy adaptor harnesses. It replaces the original circuit board inside the factory ECU enclosure and mounts using the factory brackets.


This Link G4+ Subaru WRX/STI plug-in ECU is suitable for the models listed below:


Subaru Impreza Version 7-9 WRX & STI Impreza WRX & STI (GD/GG chassis, MY2000-2007 with cam control. 2.0L models only)


Once the installation is complete, the Link G4+ allows a good tuner to achieve an optimal state of tune to get the most out of any combination of modifications.


All Link G4+ plug-in ECUs come with a base map. While these maps are designed to help save time for you and your tuner, it is essential that these are used simply as a starting point for further tuning.


The engine can easily be converted to speed density by removing the air flow meter and instead using a suitable MAP and air temperature sensor.  Likewise, this ECU can also be setup to control boost electronically with in-cabin adjustment. This eliminates the need to purchase a separate electronic boost control system.


The vehicle’s original sensors & actuators are used except for the following exceptions:


  • MAP sensor – For all models the factory MAP sensor is supported. These sensors are capable of measuring up to 1.64Bar (23.5psi) boost. If more boost is intended to be used a higher rated MAP sensor can be connected to the existing wires. The airflow sensor is not required.
  • Inlet Air Temp sensor (IAT) – An appropriate IAT sensor (available seperately), should be installed just prior the throttle body even on models that have a factory fitted IAT sensor near the airbox and even on Spec C models that typically have a factory fitted IAT sensor in the inlet manifold. The factory IAT wiring can be used on models that have a factory fitted IAT sensor. On all other models the IAT sensor can be wired via the expansion connector on the ECU using the XS loom.
  • Boost control – The factory boost solenoid control wiring is used, however the boost solenoid must be upgraded on applications using an external wastegate or elevated boost levels.
  • Injectors – The G4+ plug in is NOT designed to be used with low impedance injectors. All the Subaru models this G4+ plug-in is designed for use high impedance injectors so no changes are necessary. However if low impedance aftermarket injectors have been fitted then the correct ballast resistors MUST be fitted.



Extra sensor inputs

The expansion connectors on the Link G4+ board are provided to allow the easy connection of additional ECU inputs. The two expansion connectors on this particular plug-in model provides the following:


  • 2 x 5V Supply
  • Sensor ground
  • 3 digital inputs
  • 6 analogue voltage inputs
  • 1 analogue temperature inputs



These may be used for functions such as driver adjustable boost control, switchable fuel/ignition maps, wideband lambda input, external MAP sensor, fuel pressure and oil temp/pressure.



Any redundant outputs may be reconfigured & used for alternative uses, eg extra electric fans, intercooler water spray, shift light, water injection