Rough guide
Well, I think that The luff should be within plus or minus 8% of your 'I' dimension. Foot length should be 160 - 180% of your 'J' dimension. Of course, the luff shouldn't exceed your maximum halliard hoist. Enhanced forward visibility, and less chafe on your furling drum both argue for the low to mid-range values cited above. And, obviously, a smaller chute is easier to handle when short-handed, or when everyone is intoxicated. A longer luff, though, would probably improve your performance, especially with the wind on the beam, or forward of the beam. Cruising chutes, in my experience (with a similarly sized boat) are great for a broad reach, in moderate wind, and even a beam reach, in lighter winds. Moderate winds can overpower my boat (which is a bit 'tender') on a beam reach, although I have seen talented sailors use it effectively on this point of sail on other boats. Running downwind, some folks use the spinnaker pole.... but the reason I use a cruising chute is primarily because I don't want to rig the pole... so I keep the wind a bit to one side or another. Of course, a 'sock,' in my amateur mind,is absolutely essential. And a bag... well worth the $. I hope there was some useful information in there somewhere. Good luck - Rick
