How long have you been sailing a Windrush 14?
What spi did you use to convert it to F14?
Do you have problems with your mast permanently bending?
I am the current Australian National Champion for Supersloop and Cat rig. I also once trialed one with a Hobie 16 Spi kit, while i was in the Aust Youth Team. But we manage to put a 3-4 degree bend in the mast in 10knts with leech tension...