Dirk, Wouter & Rolf,

If you simply add the extra 700mm to the head of the old "pin" head Tornado sail, you will only gain about 50% of the potential. If you think about it, the extra sail cloth will only push the max drive point further forward & this can only be rectified by re-working the broadseaming ( as Rolfe Nislen suggested). I think sailmakers would generally prefer to either add sail cloth or make a new sail, as to re-work the seams in the head of an old sail would be very time consuming & a "stab in the dark". I inherited a modified ullman main with the marstrom tornado that I bought, which all they did was make the last radial panel larger to the wide head. I'm sure at the time the owner was satisfied mentally, but not performance wise !!!

BTW - we are going to further modify this sail for the first sail for our blade 16 to see how everything settles down.!!

Trusts this helps.

Marcus