I just called Wix filters tech line and had them look up the largest filter with the same specs as my stock oil filter for my 1982 aircooled Westy.  They came up with a winner.  Wix # 51515  its about twice the size and has the same specs for antidrain valve and for the internal bypass valve that opens between 8-11 psi.  I am going to switch over next oil change.  I think there's enough room in the stock location for it but since I have a remote filter now it will be no problem for me. 

david
1982 Westy 

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