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I found the time today to measure my injector deadtime for the injectors and configuration below. I used the procedure outlined on the MSextra web site using the Tunerstudio output test mode for injectors. I measured at the four points as outlined and then extrapolated the 0 crossing point and came up with approximately 0.30. Does this seem reasonable? I have never seen any other deadtime figures below 0.55.
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I've just built up a Porsche 914/4 2056 engine using the stock 2.0L Bosch injectors, 280-150-019 with MS3/MS3X and a JBPerf peak and hold driver board. I'm looking for a short cut on the dead time measurement for these injectors. Has anyone tested these injectors for dead time?

I have some low Z Bosch injectors on my desk that spec'd about .5ms, but they are GDi injectors off a Mazda 6. The driver kicks them on with a 100v capacitive discharge to get that low a number.
.30? highly dubious ...unless they are Piezoelectric, what are they?.

Most low Z injectors are ~.6-7ish, but all you can do is try it do the old 2/4 squirt sanity check and see if it gets richer or leaner.

If it does neither, you are about right.

They are the stock Porsche/VW 2.0L injectors which are electromagnetic devices. After I posted the original message I remeasured and came up with essentially the same value. Just to be a little on the safe side I used .35ms as the dead time value and it has worked out well for the car.

I completed my "final" tuning element today - IAC using a Bosch 3 wire PWM IAC valve and now have the car running with a reasonable 1200 rpm idle at startup and settling down to 1000 rpm's when warmed up. The engine has a Webcam 86 which does not give very much of a Map signal at idle (65 - 70) so the 1000 rpm idle is very reasonable.

I am really happy with Megasquirt 3/3X and would recommend it to anyone!