IPW = Injector pulse width - the time the injector is open for.
An injector fires once every two crankshaft revolutions.
IDC - injector duty cycle - is the % of the time duration of those two revolutions that the injector is open for.
Using IDC and injector size, you can calculate the weight of fuel being injected - and using A/F, you can calculate g/s of air.
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