Defender & Discovery 2 Td5 PSI Power Tuning Box DA4433

£334.31 ex VAT

In stock

  • Defender – Td5
  • Discovery 2 – Td5
  • Power HP – Before – 121 / After – 158
  • Power KW – Before – 90 / After – 118
  • Torque Nm – Before – 300 / After – 374

PSI Power Tuning Box

A PSI technologies power tuning box for Land Rover Defender and Discovery 2 models with the Td5 diesel engine fitted.

Works with automatic or manual transmission vehicles. The unique Power Box catches the fuelling signals from the ECU to the fuel pump and then modifies them to ensure the exact amount of diesel is supplied for enhanced performance.

This in-turn improves torque, optimises fuel consumption, reduces smoke emissions and lowers stress on the engine.

The Power Box improves torque enabling the vehicle to change gears earlier and hold higher gears at lower speeds, making driving more pleasurable.

The unit fits using the original manufacturers plugs; these existing plugs are opened and the Power Box is secured in between.

Full fitting instructions are included with every unit.


  • Plug-in unit
  • No intervention with the original ECU
  • 3-Year equipment warranty & 1-Year engine warranty on new vehicles (subject to conditions)
  • TUV approval
  • Compact size
  • Shock resistant & waterproof
  • Competitively priced


  • Can be removed prior to sale or used as a selling point
  • Traceless
  • Peace of mind
  • Quality product which is legal & safe
  • Unobtrusive in interior of vehicle
  • No worries off road
  • A good investment

Performance Figures:

  • Power HP – Before – 121 / After – 158
  • Power KW – Before – 90 / After – 118
  • Torque Nm – Before – 300 / After – 374

Part number DA4433

**Please ensure you are buying the correct part**

For exact change over points with vehicle applications please contact us with the full chassis number for the correct application.

Additional information

Weight0.72 kg
Dimensions190 × 135 × 70 mm





Defender, Discovery


Defender 90, Defender 110, Defender 130, Discovery 2

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Stated product weight may vary from the actual weight of the product. This is because we use volumetric weight to calculate shipping costs. Please get in touch with us directly if you need the exact weight of product.

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