ok, so i managed to speak to my mechanic this evening. (He's a great chap, and very good, but difficult to get hold of!!)
he agrees with what has been said, reduce the prop pitch to 13, and that should give me another 500revs. this should then be enough to get her up on the plane, and then she will pick up from there.
did really rate the hydrofoils, but i did not have time to talk about why they won't help??
maybe you know more about this.
he also said i need a tacho. he has an old one knocking about that he will bang on, so i can see what the engine is doing etc
so i will let you know how i get on. maybe a while though, as we are away for a few weeks
thanks for all your help
shame there is no reputation system on this forum, 'cause some of you would be getting greenies !!!