1 microsecond, or µsec, = 1.0 × 10-6 seconds. Simply 1 µsec = 0.000001 seconds.
This is territory I haven't entered yet, but the MPGuino guys will answer this better than I can. I believe that Injector pulses are 2 pulses per rotation, open and close, and this is part of the rpm, so 6000 pulses would be 3000 Rpm, then a certain number of pulses = 1 gallon of fuel dispensed.
I hope I am right, but please disregard If I am later proven incorrect. I know I am right on the conversion though
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