I have a few old wind surf sails that match my luff curve on my 4 meter sail. I'm thinking about a 3 m 3.5m sail for heavy air. It looks like most of the heavy air sails I've seen are regular shaped sail cut down at the foot of the sail. This could easily be done with the sails I have. What if I left the height the same and cut more of the roach off to achieve the sail size I'm after? Maintain a high aspect ratio, lower the Center of effort and sail size all at the same time.
Just a thought, also try reducing the Foot length along the boom, this will make the sail easier to sheet in and reduce sail twist.
The boom could remain at its original length.
given that your in the US and probably going to sail in high winds on a clay lake . Very hard and fast i would go with the shorter sail option. in a good wind you might just discover that a tall skinny sail can bite you in the bum. they have a habit of trying to sail faster than the lump hanging on the bottom of the mast ,leading to pitchpoling.
on a mini landyacht , I now call this "releasing the ninja." it hurts, and can lose you a marathon , especially if you do twice in the same race
