38 is tiny for the 110 !! I am using 44cm Z-Fin with 7.0/7.8 and 46cm with 8.6m ...
A bigger fin definitely gives you more lift, earlier planing and more drive through the lulls; it helps to power the board up and get it railing and a bigger fin is much easier to pump against in light winds.
What size sails are you running on your 110?
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