We also had the machine shop drill two holes in the block between the center cylinders. The holes lead directly into the water jacket and will correspond with two holes we had drilled in the cylinder heads. This will allow additional water circulation between the two center cylinders, relieving a hot spot caused by the two adjoining exhaust valves. Modern Y-Block head gaskets have these holes and there are usually detailed instructions included that show how to locate and drill both the block and heads.
The crankshaft was turned .010" on the main and .020" on the connecting rod bearing surfaces and we used a good set of Clevite 77 bearings. We also had the engine machine shop install new Clevite cam bearings as well. The connecting rods were fitted with new ARP high tensile strength rod bolts and then resized before the entire reciprocating assembly was balanced. The balancing ensures that all of the piston assemblies (piston, pin, rod, rings bearings) are of equal weight. If you've ever heard the phrase that, "it runs so smooth you could put a coffee cup on top of the air cleaner and not spill a drop", that's a well balanced engine. In our case we used two connecting rods from a different engine and wanted to be sure everything balanced out, so there wasn't any chance of a rough running engine.
