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Rebuilding a olds 350. Under the intake there are 2 holes. One goes to the #2 cam bearing the other goes to the #4 cam bearing. What are these holes for? My cam bearings only have 1 hole. Should they face the crank or the top end holes?
The 1964-67 330 motors used a three piece intake gasket - separate metal embossed gaskets around the ports and a large center tray that was held with those fasteners. It's not the same as the little deflector used on the BBOs. And of course the later roller cam motors (gas and diesel) use those holes to retain the spider for the roller lifters.
Its a 70 block. They are not threaded, and I can see the cam bearings when looking in the holes. My concern is, do I have the right cam bearings? Should there be 2 holes in the bearings, 1on top and 1 on bottom? Why are the holes there? If they don't feed oil to the cam then oil would just sit in the holes and do nothing, whats the point of that.
You do not want the holes in the cam bearings to face those holes in the block. The holes in the cam bearings face the crankshaft for proper pressurized oil delivery to the camshaft bearing.
Just leftovers from earlier versions of the mold. They don't change details of the mold making stuff unless they need to.
The hole in the bearing faces the oil feed, which comes from the main bearing - so the hole in the cam bearing faces down. Your machinist that's installing the bearings will know this.
You don't want an extra hole in the bearing. It would just spit away oil.