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24-10-2006, 08:29 AM
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#41
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Registered User
Country: England
Location: South West
Occupation: Development engineer
Interests: Fast boats
Boat name: Xtreme
Boat make: Bernico 21
Engines: Mercury F1, 300 Drag, XR2 "Fingerported"
Cruising area: South West
Join Date: Mar 2004
Location: South West
Posts: 1,043
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Who is racing and on what day?
Quiet fancy a trip up for a day.
Puppies no prices as yet as i have not yet had the hull measurments, will let you know once done.
Cyco
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24-10-2006, 09:26 AM
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#42
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Member
Country: uk
Location: brighton
Occupation: derivatives trader
Interests: powerboating & ice hockey
Boat name: marex for this year
Boat make: wonky shed cowdron
Engines: twin merc 250 opti xs
Cruising area: southcoast & europe
Join Date: Aug 2006
Location: brighton
Posts: 87
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The difference between a speedboat and a powerboat is easy to define....its time spent at the fuel pontoon divided by weight and length.....if it hurts u its a powerboat!!!!!!!!!!
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24-10-2006, 09:31 AM
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#43
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numbskull
Country: United Kingdom
Location: South
Occupation: none
Interests: none
Boat name: Leviathan
Boat make: Phantom 28
Cruising area: South Coast
Join Date: Mar 2004
Location: South
Posts: 15,959
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So Matts Formula is a powerboat, and mine isn't!
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24-10-2006, 01:41 PM
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#44
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Senior Member
Join Date: May 2006
Posts: 277
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Quote:
Originally posted by Jon Fuller
So Matts Formula is a powerboat, and mine isn't!
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Correct! 
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24-10-2006, 01:46 PM
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#45
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Senior Member
Join Date: May 2006
Posts: 277
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Puppie could go for :
Outboard Immersed Prop Mono
or possibly
Superclub Monohull Unlimited
Current record is something like 78.33mph
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24-10-2006, 01:50 PM
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#46
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numbskull
Country: United Kingdom
Location: South
Occupation: none
Interests: none
Boat name: Leviathan
Boat make: Phantom 28
Cruising area: South Coast
Join Date: Mar 2004
Location: South
Posts: 15,959
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Quote:
Originally posted by FabFour
Correct!
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Shut it Lanky! 
__________________
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"I Agree with everything you say really!" - John Cooke to Jon Fuller - 26-01-2013
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24-10-2006, 02:06 PM
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#47
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Registered User
Country: England
Location: Poole
Interests: Going fast
Boat make: 31 foot sports boat
Engines: 15 Litres of gas guzzlers
Cruising area: Poole Bay
Join Date: Oct 2006
Location: Poole
Posts: 45
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Insurance industry generally treats anything that goes faster than 17 kn (20 MPH) as a speedboat. I therefore assume that as Speedboats are fast Powerboats (according to every dictionary I've read) that Powerboats do less than 20 MPH !!
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24-10-2006, 04:16 PM
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#48
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Senior Member
Join Date: May 2006
Posts: 277
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( we need a 'laughing with impunity' smilie... )
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24-10-2006, 04:54 PM
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#49
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Registered User
Boat make: Phantom 23
Join Date: Mar 2006
Posts: 1,693
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Quote:
Originally posted by FabFour
Puppie could go for :
Outboard Immersed Prop Mono
or possibly
Superclub Monohull Unlimited
Current record is something like 78.33mph
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cool, all we need now is our new prop!
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24-10-2006, 05:54 PM
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#50
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hello
Join Date: Mar 2004
Posts: 2,739
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Wouldn't worry about that too much if you're doing 94 on the one you've got!!!
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24-10-2006, 05:58 PM
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#51
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Registered User
Boat make: Phantom 23
Join Date: Mar 2006
Posts: 1,693
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but the motas revving abit high.
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24-10-2006, 06:00 PM
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#52
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hello
Join Date: Mar 2004
Posts: 2,739
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How high? Its only a few short runs.
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24-10-2006, 06:03 PM
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#53
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Registered User
Boat make: Phantom 23
Join Date: Mar 2006
Posts: 1,693
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7K, Wayne says it will be fine upto 7500 but thats not where max speed is. we could get it to 7500 with the curent prop and same load it was just the sea conditions that was holding us back last time.
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24-10-2006, 08:35 PM
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#54
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Registered User
Country: England
Location: Hertfordshire
Occupation: Airline Operations.
Interests: Rum. Pirates. And West Cornwall pasties.
Boat name: Any suggestions?
Boat make: Ring 18
Engines: Mercury 200 Black Max
Cruising area: The Bay of 'E'
Join Date: Sep 2005
Location: Hertfordshire
Posts: 369
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Quote:
Originally posted by Jon Fuller
A ring is a speedboat, a PHANTOM is a POWERBOAT! obvious!  
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.Taking cover!
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Oi! 
Grrrrrr.........
__________________
Boat: (Noun) - A hole in the water, lined with fibreglass, into which you pour money.
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27-10-2006, 11:21 AM
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#55
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Registered User
Country: Spain
Join Date: Sep 2005
Posts: 1,726
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The one with the number on the side is a powerboat.
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29-10-2006, 04:32 PM
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#56
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Registered User
Country: England
Location: Crayford, Kent.
Occupation: Electrical gezza!
Interests: Petrolhead
Boat name: Wayne Kerr
Boat make: Phantom xl
Engines: Mercury 2.5, 200(ish)
Cruising area: Essex, Hampshire, Mediterranean
Join Date: Sep 2004
Location: Crayford, Kent.
Posts: 1,199
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29-10-2006, 05:26 PM
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#57
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Registered User
Country: Essex
Location: Great Stambridge Essex
Occupation: Director Paving company
Interests: Boating/Squash
Cruising area: Essex Marina/crouch southeast coast
Join Date: Sep 2004
Location: Great Stambridge Essex
Posts: 2,033
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What prop are you runnin at 7k to achive 94mph??
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29-10-2006, 09:01 PM
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#58
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Registered User
Boat make: Phantom 23
Join Date: Mar 2006
Posts: 1,693
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26" yam drag
heres how to work out speeds
7k(RPM)
/
1.615(GEAR RATIO)
x
26(PROP)
x
60(GIVES INCH PER HOUR)
/
63360(INCHES IN A MILE)
=
106.71732807955718172436438690309
x
0.88(12 % SLIP)
=
93.911248710010319917440660474716
which is 94mph 
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29-10-2006, 09:30 PM
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#59
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Registered User
Join Date: Mar 2004
Posts: 5,724
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Quote:
Originally posted by PuppiesBalls
26" yam drag
heres how to work out speeds
7k(RPM)
/
1.615(GEAR RATIO)
x
26(PROP)
x
60(GIVES INCH PER HOUR)
/
63360(INCHES IN A MILE)
=
106.71732807955718172436438690309
x
0.88(12 % SLIP)
=
93.911248710010319917440660474716
which is 94mph
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so mine is.........
5950 RPM
/
1.87
x
24 prop
x
60 Inch per hour
/
63360 inches in mile
=
72.3140496
x
0.95 (5%) slip
= 68.6983471
Actual speed recorded on gps was 68.9mph
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29-10-2006, 09:39 PM
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#60
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Registered User
Country: England
Location: Kent
Occupation: Train Engineer
Interests: Refit/Re-engine Woody's P18 and helping with D2S.
Boat name: Fugazi II / D2S
Boat make: Phantom 18 / Planatec 41'
Engines: 1xMercury XR2 / 2x 8.1ltr Chevys
Cruising area: Kent/Hampshire/Dorset Coasts
Join Date: Aug 2005
Location: Kent
Posts: 411
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Quote:
Originally posted by PuppiesBalls
(12 % SLIP)
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You're doing very well to acheive 12% slip. Do you use SuperGlue on the blades? lol.
I was once told that the slip factor was at least 15%.
The formula that I was given 16+ years ago is this:-
Revs x Pitch x 0.0004734 = m.p.h.
m.p.h. x Slip Factor = true m.p.h.
I suppose thats not too dissimilar to your formula.
I suppose the only way to find the true slip factor of a prop is to usegps to get the speed. note revs and work formula backwards!!
Graham.
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