here are the following PHRF ratings that we used for last years races: CP16-----326 Suncat----320 Eclipse----288 CP19 ----279 and CP 23-----249. We started the slower 16s first and based the other start times with the 16s. Suncats would start 24 seconds after the 16s, the Eclipses would start 2 min 30 seconds after the 16s, the CP 19s would start 2 minutes and 45 seconds behind the 16s and the CP 23 would start 5 minutes behind the 16s. i would ask Mattman to review these numbers as he has the most race experience . the skipper of the fastest boat (the 23) would be the race start official.