Before I make a lot of extra work for myself - putting my 1970 455 back together today. Using a std Felpro gasket set. When I dry fit the head gasket I see it is fully or partially covering water passages that have matching openings on the heads. Is this normal?

 

Yes this is normal. The head gasket will direct the flow of the coolant so it gets everywhere in the head.

 

That is completely normal. The holes are mostly there for the casting sand to come out of the block and heads and are larger than needed for coolant. The holes in the gaskets are designed to flow the proper amounts of coolant through the holes.

 

Coolant flow in Olds motors runs from the water pump rearward in the block around the cylinders, up into the heads, and forward to the intake water crossover and thermostat. The holes in the gasket between the head and the block need to restrict the flow of water from the block to the heads. If it didn't, all the coolant would flow upwards at the first opportunity, causing the flow to the rear cylinders and combustion chambers to stagnate, resulting in overheating at those locations. The engineers who designed the engine (and the gaskets for it) were not stupid. FelPro has been making these gaskets for decades, and if you look at the old OEM gaskets that came out of the engine, the holes are the same.

 

Thanks for info , was also thinking to buy Fel-Pro gaskets to the 425.

 

10-4 thanks to all