The sailmaker should know
Any sailmaker should be able to tell you those dimensions if you supply the rig dimensions for your boat. For the Oday 23 (later model): I: 28.0' P: 23.5' E: 9.0' J: 10.0' There may be a calculator on the internet that can do the same thing. I did find one that lets you plug in the rig dimensions, and it gives you the sail area, but it didn't allow you to specify that you wanted a greater than 100% jib. Using the link below, I found that the Oday 23 has a jib square footage of 140, and the main is 105.75 sq. ft. I think there are some twists to the actual sail dimension calculations, but that a 150% jib is about 50% bigger than a 100% jib. If this is true, then a 150% jib would be about 210 sq. ft. for the Oday 23. The actual dimensions? The possibilities are infinite. When I bought my new 135 genny, the sailmaker told me the dimensions after measuring at my boat. He took into account the placement of my life lines, furling unit, bow pulpit and existing sheet blocks.
