comb filter for pitch detection

Hi,

I am trying to create a pitch detection patch (I realise fiddle exists) that uses a series of tweleve comb filters, one corrosponding to each pitch in an octave. Then by figuring out which filter produced the signal with the maximum power, I can make a guess at what the pitch of the incoming signal is.

I have everything for the patch mostly working, however, I cannot figure out how to use comb filters...

Can anyone give me a hand determining what the values passed into the comb filter will be so that I can get a filter that only allows through frequencies that would line up with a pitch's fundamental frequency and overtones?