[oldbeaver]

Dear dieseler's,

To me all sensors mentioned are ok: pressure, sound or piezo. However, the less invasive and the simpler the better. The piezo electric seems to me to have some advantage as piezo adapters and timing lights for diesels already exist. This should ease the transducing part of the process with piezo sensors, in comparison to the other two.

But, some working with the signal may be necessary anyway. The graph published by P-hack probably represents the situation. If vibration is like the graph, we should be able to convert that into digital pulses representing injected volume.

To make it simple: we may think that the fuel injected is proportional to the area under the curve. If that is true, we need to get duration of pulse and mean voltage generated. And we need to count number of pulses per unit of time, of course.

I would study in the oscilloscope what happen with the injection pulses under different loads. My only concern with this signal is: would the graph get that variation? If so, there should be a variation on the voltage generated.

AndrzejM believes that sound on injectors should vary with load, so signal generated on the mike devoted to capture it. I think he is right. However, working that signal should be a lot harder.

On the other hand, the pressure sensor proposed by TheTestPilot may probably be the most direct and "true" measure of injected volume per stroke. However, this tranducer looks the hardest to manage to me.

Question to P-Hack: what source for that piezo timing light systems do you know?

Oldbeaver