The concept to be taken into account is that a chassis dynamometer, whatever it is, always measures a power at the wheel and not an engine power.
If you want to obtain engine power directly, you must then go to an engine test bed (which we also offer)
To allow an estimate of the engine power on a chassis dynamometer, the test breaks down as follows:
During the first phase of the measurement, we will speed up. The dyno will then measure a force at the wheel.
The second phase is the measurement of losses: by letting the vehicle decelerate, a “lost” force is estimated between the engine output and the dyno sensors (hence “loss acquisition”).
Engine power is then the power that we measured at the wheel, weighted by this loss factor that we have calculated.
Note that Rotronics is able to offer you a much faster acquisition of losses (of the order of ten seconds) than what is done with the competition, which will allow you to make several power shots much faster. .
All Rotronics dynos offer loss acquisition (even hub dynos)