I have always used AC/Delco PH25 filters on my small block Chevy's, but since they have been discontinued, I have been using the part # suggested replacement for the PH25 (small block V8 filter) which is the 454. But the 454 definately is not as big, and does not have the capacity of the 25. I was thinking of maybe a Purolator, Wix or Mobil 1 filter. I run the 15W-50 Mobil 1 oil in the Boss. I was wondering what is the filter of choice for you guys?