No. When the sand casting is first made, it gets a -1. After a few blocks, one of the cylinders invariably collapse. It is replaced and the block gets a -2. This means your block was cast from a mold that had 5 cylinders replaced. Of course, the -1 and -2 blocks are the least likely to have core shift -- thin cylinder walls on one side. The TA 340 blocks were all -1 or -2 blocks (from what I've seen).