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We are in the process of building a 68 396. The FelPro head gasket set that we have states that the block must have 3 lower coolant holes in the block or that they must be added if they are missing. We do not have the 3 lower coolant holes. Can someone shed some light on this as we are hesitant to start drilling holes in the block? Thanks in advance!

Nobody??

I'm trying to remember, its been awhile, one way to get an idea, is to line the gasket up to the head, and mark with holes line up with the gasket, then do the same on the block, and take note of which holes are not present on the block, then go from there, I would tho suggest not drilling them free hand, but if you do, put rags into the cylinders, keep a tri-square handy, or try to make a guide for the drill to keep it straight,

Tap the center of the spot to drill with a center punch and drill a pilot hole first to ensure the your hole is properly centered.

Thanks for the feedback guys! It is not that I am worried about how to go about drilling the holes as much as the question of is it really necessary. From what I have been able to find out, only the early 396 castings did not have these holes. Was it a design change that GM made to improve cooling of the heads?

Are the coolant holes in the heads? If not then I probably wouldn't drill.