Injector dead time - how to read that without factory data?

Hello!
I have new injectors from aliexpress 800cc/min side feed for subaru (yellow) 16600-AA170 and have no more data.
I think to assembly these to fuel rail and do measurement. But with Output test I don’t have precision opening times to make measurements in which time thay opens and inject some fuel out (fuel rail is outside engine).
Is it good measurement to set opening time from 0,4 ms and add 0,1 until fuel goes out? And when fuel starts going out by for example 0,9ms than approximate injector opening time is 0,8ms. All measurements with 13,8 volt stabisiled supply connected to baterry and 43 psi fuel press.
If this method is correct, it would be very good if the ECUMaster added this option in the software.

It is better to inject for example 100 times 2ms and 100 times 4ms. Then based on injected volume you can easily calculatee the dead time. It takes into consideration both opening and closing time.

Other method is current probe.
Monitoring current with the scope when injector opens, you can spot easily the point when the needle starts to move.

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It’s also possible to get extremely close dead time data with a knock sensor pressed against the injector body and an oscilloscope hooked to injector output and knock sensor. This won’t tell you about fuel flow, though.

See this video from Shane Tecklenburg. I used ID1300 injectors and entered exactly the data published from their website. This had 1.035ms at 14v 3Bar pressure. I noticed fluctuations with O2 when my headlights turned on. After going through Shane’s method, I measured 0.60ms dead time at 14v 3Bar. Way, way off! It was hard to believe, but now I don’t care what data I find even from ID. I’ll be testing from now on. Backed up my results with batch injection vs sequential for both dead time data and found that my dead time with Shane’s directions gave very close real dead time values.

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Very nice methode. Gone try it out as well !!