I was told to supply enough oil to my top end of my 65-66 396 big block i need a groove cut in to the rear journal of my camshaft. The bearing already has the groove. Right now i have no oiling to my oil galley that fills the lifters priming it i get 55psi but very little oil comes out the passages at the top.

 

This page has a lot of useful information, including early bbc cam groove requirements.

http://www.mortec.com/notepg3.htm