engine issues, help please!

You never mentioned bize so i,ll assume its a small block. B/rb motors dont have watrr passing thru the intake. it is a possibility its the intake gasket but that would only put water in oil and not the cylinder. Pull your plugs and use a compression gauge to check cranking cylinder pressure .If all cylinders are high and uniform ,not sure but probably 150 to 220 depending on compression ratio then its not head or cylinder related.For your sake i hope it is because if it lost power due to compression then head gaskets should fix it but if bearings are galling due to lubrication problems ie water in the oil the block is going to have to be torn down.