Hello  I have  std bore 312 block that has been freeze cracked. I don't know why I saved it (30 years) but I did. The crack is about 2 1/2" long on right front edge (flat part) just before where right side starts. It is a very fine crack, unless you hot tanked it or really looked hard, probably would not see it. Any way, does any one here had any info or advice on fixing it or junking it? I have researched a little using stitch and lock. They make it look easy BUT I have been told that is easy to break taps off, that where trouble starts.  It will cost over a hundred dollars for parts if nothing goes wrong. Iam thinking it is not worth risk and sent it to China. Bill  Oregon