Thank you for your explainations. You are getting to be very informative.

Here is a few more information

RPM
Min?Max-3000rpm
What would the best xtal I should use? I am currently running a 10MHz 18pF xtal.

Signal conditioning.
None at the moment. I have the sensor directly connected to PORTA.4.
I think I should be thinking of cleaning up the signal. Maybe a LM3??, forgot which one. Shouldn't be to hard to find out. I have in paper somewhere.

Another question I have is that, does the PIC have the capability of Input Capture of either raising edge of a signal or falling edge?
I will try to look it up. Thought I will ask you if you happen to know of the top of your head.

Thanks again
Randy