This test compared two ways of changing the performance of a Volkswagen Sharan 1.9 TDI: an aftermarket power box bought online and an engine control unit remap. The initial dynamometer reading was 146 hp and 337 Nm.

A resistor was found inside the box. It connects to the fuel temperature sensor circuit and alters the signal received by the engine control unit. With the device fitted, the dyno showed 157 hp and 387 Nm, an increase of 11 hp and 50 Nm over the initial result. After removing the box and remapping the ECU, the result was 178 hp; the video gives torque at approximately 480–490 Nm.

This is a comparison on one vehicle, not a universal promise for every power box or calibration. Fuel consumption was not measured separately during the test, so the dyno figures alone cannot establish a fuel economy benefit.