Francesco,
At the risk of stealing Sandy's thunder, it is not a matter of matching films to Pyrocat dilutions so much as matching dilutions for desired density ranges in the negatives. 1-1-100 dilution is typically used for negatives designed for enlarging. (DR of 1.00). The 2-2-100 dilution is designed for negatives that have higher desired density ranges (Azo, Pt-pd, Carbon etc.) I am not sure what you are doing with your negatives. This is a general explanation.