Reply
 
Thread Tools Search this Thread
 
Old 08 July 2007, 14:54   #11
Member
 
Country: UK - England
Town: Mighty Penryn
Boat name: Little Joe.
Make: Avon Searider
Length: 4m +
Engine: Honda BF50
Join Date: Aug 2005
Posts: 8,841
Quote:
Originally Posted by Flavio View Post
I'm a big boy and if I want to put 300hp on a 200hp rated boat it's my decision.
You must be a very big boy!
__________________

__________________
Mollers is offline   Reply With Quote
Old 08 July 2007, 15:27   #12
Member
 
Country: UK - Wales
Town: swansea
Boat name: Too Blue
Make: BLANK
Length: 8m +
Engine: Suzuki DT225
Join Date: Mar 2004
Posts: 12,791
Well obviously the smaller the prop diameter goes the higher the RPM. 4 strokes tend to provide more thrust at lower RPM which is why they tend to have bigger diameter props.

Obviously a larger diameter prop will provide more drag so to go faster it's smaller diameter bigger pitch you need.
__________________

__________________
codprawn is offline   Reply With Quote
Old 14 July 2007, 07:55   #13
Member
 
Country: UK - Scotland
Town: Ayrshire
Boat name: Raven
Make: Ribcraft
Length: 5m +
Engine: 150 suzuki
MMSI: 235040525
Join Date: Aug 2006
Posts: 653
Quote:
Originally Posted by Flavio View Post
Thanks for all the comments. I'm a big boy and if I want to put 300hp on a 200hp rated boat it's my decision.

Unfortunately no one has answered my question what effect on rpm a smaller diameter prop would have. There must be some rule of thumb for this just as there is for going up or down in pitch?

I tested the boat again today and apart from some mild chine walking at maximum trim the boat feels absolutely safe at any speed.

BTW It is the 65 Suite model.
Your not a little overpowered you 50% overpowered which is enormous I would be inclined to ask the manufacturer of the boat after explaining your experience to them why it's rated at 200. There may be a very good reason we all here haven't touched on, better to know before you do a tripple salco with half turn out the thing as mollers says.

If the boats handling the power easily I think the prop you've got must be crap if you go down in diameter the (and I could be wrong here,but it's my experience) the slip will increase and you gain nothing. I have a similar problem and have gone down the hydromotive 4 blader route. I'll post results when I have them.
__________________
.
IBWET is offline   Reply With Quote
Old 14 July 2007, 09:48   #14
Member
 
Country: UK - Wales
Town: swansea
Boat name: Too Blue
Make: BLANK
Length: 8m +
Engine: Suzuki DT225
Join Date: Mar 2004
Posts: 12,791
It could be the 300s weren't around when the boat was designed - also most companies err on the side of caution these days. Remember the 300 weighs not much more than a 200 and less than a Verado 200 straight 6!!!
__________________
codprawn is offline   Reply With Quote
Old 21 July 2007, 07:02   #15
Member
 
Country: Norway
Town: Farstad
Boat name: Searafting
Make: Humber Offshore 8,5
Length: 8m +
Engine: 2 x 250 Suzuki
Join Date: Jul 2004
Posts: 68
If you want realy go fast props try 25" Mercury revelution 4 prop with Suzuki hub or a Mercury bravo one with Suzuki hub, the revelution 4 is faster than than the Bravo one, you could get the revelution 4 up to 25" pitch.
__________________

__________________
searafting.no is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 23:07.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.