on a small you almost need to run a tube through the lifter oil galley to block off oil, but on a big block, more so than not, you can get away with doing less. I bought my crower cam .630 .645 off ebay with springs and retainers, for a mere $120 with shipping used, and got a used set of solid crane roller lifters at the swap meet for $125. I did have to buy a bronze dist. drive with was like $75. But let me tell you the combo I put together and ran it both on the street and at the track was unreal!!! roughly 600 hp