What size prop?

[Guest]

I'm looking for some advice! I have just had a new engine installed in my Fairline Sprint, a V8 Volvo 225. Prior to this I had a V6 205 running thru a 290 leg with a B5 duo prop. I found that with the "new" engine the revs were very high (admittedly the rear prop has a bit of damage) and despite resetting the rev counter for a V8, the situation continued. I am currently running a a B8 set which now only revs to 2700 but cruises comforably at 2000 doing 25 knots. My question is how can I best determine the optimum prop size for the boat, engine and leg combination? Any help, advice or contacts would be much appreciated.

Thanks

 

[Guest]

David,

Powerful boats such as yours probably need to be propped by experts with computers rather than most of us who own non planing boats.

If you really want to get into it I can recommend a book solely on props that I have had out of the local library a few times -:

Propeller Handbook by Dave Gerr
ISBN 0-7136-5751-0

It is very interesting reading and might save you a few quid.

 

[Guest]

Thanks Vic.