Official Sail Measurements

not sure about factory specs but i would be suspicious of any "standard".  the sail loft i work for measures every boat we make sails for, even production boats because there is considerable variation among boats of the same class.  sometimes the wrong mast goes on a new boat!  you'd be suprised.  anyway, actually measuring will save you from having new sails recut or improper fit.

find a local sailmaker and talk to him or her about the kind of sailing you do.  your sailing style and local conditions are the most important factors.

best of luck,
cody