Pulse rate for rev counter help ?

[Ian.p]

Does anyone know the pulse rate for the rev counter ,I’ve a friend who could make the original rev counter work on my engine swapped car from the obd port he just needs this bit of into if anyone has the knowledge ?
thanks Ian

[Doctordiesel77]

The original rev counter is wired to coil negative, so one pulse every time a plug fires, each cylinder fires once every two revs, so should be 4 pulses per two revs, ie 2 pulses per rev, unless I've overlooked something..
.good luck
John