lifter galley crossover tube
On the BB I block the left lifter galley completely off (only with solid lifters), and I slot the holes for the rockers as it's only # 4 cam but only about a 1/4 - 3/8 " not all the way around the rockers don't need that much oil. If you look at a Hemi cam vs a BB cam the Hemi has a small groove around the #4 journal very small and It feeds 4 rocker shafts.