What other op amps can be used for a better performance..??
As this project should not fail...
I found that if the interrupt pin wire is too long it receives a lot of EMI and HV pulses from the surroundings..
The circuit above is using an SCR to pickup only HV pulses as it will be picking pulses from the ignition output..
In my case it is all low voltage ac pulses.. so i think the SCR is not needed..