There is also misinformation in the older books. This is where the myth of thin wall casted blocks came from. Several different statements are made in the older printing in regards to the thin wall theory. The truth is any block could be thin or thick. It's also rather ironic that the lowly smog 400 is structuraly much stronger than any 440 or 383 block ever produced. This is the kind of information lacking in an old printing.