What we typically do with modifying cats to the F16 rule/performance is take the Texel handicap calculator and start adjusting parameters until we approach the F16 handicap of 102.

But a little knowlegde of sailbaot design is handy. OF course a bigger jib doesn't help that much when you sailing downwind with a spinnaker.

>>How can a Cat. be modify to be a compatible F16 cat?

Often the problem is not to be compatible but to be close in performance. F16 rules do enclose alot of the 16 foots cats on the water today but it also outperforms all of them.


>>In fact I want to do the same with my blast.

I've looked at the blast and I think that it is pretty limited in adjustment because of its weight and short mast. The weight can not be changed of course and the short mast limits mainsail area and spinnaker luff length. These two are very important in boosting performance. The Nacra 5.0 has a significantly taller mainsail luff length.

>>13 sq.mrt mail sail is good one up handled.

How much do you weight ?

Wouter