Electronic Transmission Control

ACR as a natural progression from providing engine control systems, have developed an innovative product to control the electronic solenoids and valves found within modern electronic transmissions.

The original control boxes used by car manufacturers to operate these gearboxes are too integrated with the vehicle to enable the use of the gearbox for a conversion or competition car. Additionally the characteristics of a road car with its soft slow gear change and lack of a truly manual control are less suited to use for competition use.

Our system controls the complex functions of the electronic valve body within the gearbox to provide a completely tunable solution. We can increase the gear change speed and firmness, give total control over the change points and parameters, allow a semi-automatic clutchless manual operation, and run the torque converter locked or unlocked in whatever gears or speed needed to suit the application. Many more functions are possible to suit a custom application.


  • Switchable calibrations such as a sport / cruise mode, or a selectable torque converter lock up strategy.
  • Array of inputs and outputs to include speedometer driver, cooling system control, mode switches, engine speed and engine load etc.
  • Paddle shifter, steering wheel buttons or sequential shift lever options.
  • Full throttle full power gear change, or with option to control or cut engine torque during the gear change via engine management interface – for either gearbox life or avoidance of traction loss through shock load during the gear change.
  • CAN network compatibility – send and receive data to engine management or dashboard on a twisted pair wire automotive network.
  • True manual control, with programmable overrides to ignore gear change requests which could overspeed or damage the engine.


The list below are the models of gearboxes currently covered. Contact us if you have an application in mind.

  • ZF 4 HP 22 / 24 E
  • ZF 5 HP 24 E
  • Jatco Freelander / Rover application
  • GM 6L 80 / 90 E This box retains the original controller mounted inside the gearbox case. We can supply an engine management system for the LS range of GM V 8 engines with the CAN code embedded to operate this gearbox.


Prices for a wiring harness, calibration and controller from £1,350

All prices quoted exclude VAT