RE: bigger fin on carve 144l 07
I would agree with Phill and Steve's coments as above. While it's possible to use (and gain some minor low end range) benefit with a larger fin (say~52/55cm) on the C144 with 7.2m, for sure the main (and potentially marginal over stock or similar size fin) benefit will come when the larger fin is used together with the largest sail(8,5) combo.
It's important to note if you're feeling your way with fin selection /tuning etc that the Carves (with a narrower tail and stance) have a more reactive and playful ride, but don't handle bigger fins as well as (say...) similar volume (sized) boards like iSonic or F-Types etc.
Please let us know if you have any more questions or requests for this, or any other tuning etc.
Have fun ! Cheers ~ Ian