Originally Posted by Richard B
We're running a 19" (see our web site for more info). Our old 21" only allowed the revs up to 4800.
Oh dear, confusion rules.
I'm afraid that what your using on your motor has no relevance to this at all.
Apart from having 25hp more than you, codprawn also has 500 more revs to play with, almost certainly has a different ratio to you and as far as I know has a different boat as well!!
If it helps I had a 23" Lazer on my Phantom!