I have just replaced my valve covers on my 56 272 and I noticed that there is no breather hole on either one of them like the original one did, which had a hole one of them. The old system had a hole in one valve cover for the breather that branches off into two hoses which both ran into the intake manifold. My question is is that original setup necessary or am i ok without it and just using my new valve covers? any help would be greatly appreciated