Here is how you decide what size you need...
"Tool Diameter is determined by the bore size you are working with. Flex-Hones do not cover a range of sizes. The proper size tool is critical for achieving the highest overall performance and tool life. For example, a 1" Flex-Hone size is ordered if a 1" bore is to be finished and the tool is provided oversized. If the bore size is between standard Flex-Hone sizes, the next larger standard Flex-Hone should be selected. For instance, if the nominal bore is 1.093", then the 1-1/8" Flex-Hone is ordered."
The only diamond impregnated hone are used on Mercosil block as you do not hone Nicasil or chrome plated cylinders for outboards...scotch bright only