It does have 5 holes. You can plug or open any or all of them and change the hole size just by using some brass 6/32 set screws drilled to whatever size you want.
I decided at one point I needed more emulsion so I used 4 of the 5 holes in my blocks and started with a .034 hole and went down to a .028 hole in the bottom.
I can tell you it didn't work for ****. I'm not sure how I came up with the math for that but I went back to 2 holes of .026 each. I may try one more hole in the bottom to clean up the upper end of the fuel curve but at this point I have other stuff I want to try.
