Boatmad.com


Reply
 
Thread Tools Display Modes
 
Old 21-07-2006, 10:55 PM   #1
Registered User
 
MrRob's Avatar
 
Country: England
Location: Birmingham
Occupation: Scratching
Interests: Big Dinners
Boat name: Never Enough
Boat make: Seaquel 600xs
Engines: 225hp Merc ProMax
Cruising area: Anywhere! I prefer Weymouth

Join Date: May 2005
Location: Birmingham
Posts: 3,232
Send a message via AIM to MrRob
2.1 Gear Ratio

I have the option of a 2.1 gear box and I have noticed a few racers running 2.1 so can someone please explain the pros & cons of runnning a 2.1.

Thanks guys!
__________________

__________________
I got jumper cables!
MrRob is offline   Reply With Quote
Old 21-07-2006, 11:56 PM   #2
Senior Member
 
hutchy's Avatar
 
Location: the narf
Occupation: give up
Interests: triple rigs
Boat name: which one
Boat make: 25 phantom 26 puma cat,30 pima cat,25 phantom 30 flipper,
Engines: triple 2.5 efis
Cruising area: blackpool prom at dusk

Join Date: Jun 2004
Location: the narf
Posts: 244
2:1 needed when more revs needed,heavy boats or fat feckers,in boat
__________________

hutchy is offline   Reply With Quote
Old 22-07-2006, 01:16 AM   #3
Registered User
 
RossM's Avatar
 
Boat make: Phantom 23

Join Date: Mar 2006
Posts: 1,650
Send a message via MSN to RossM
Re: 2.1 Gear Ratio

Quote:
Originally posted by MrRob
I have the option of a 2.1 gear box and I have noticed a few racers running 2.1 so can someone please explain the pros & cons of runnning a 2.1.

Thanks guys!
Its because there is an optimum pitch prop which I think it 27",
For example every time a prop completes 1 full rotatation you loose X amount of speed/engine rpm from the drag of the blades and weight of spinning prop etc.

So the smaller 25" prop turning faster on a 1.87 ratio is less efficient then a 27" on 2:1 ration
so even if the engine with the faster turning 25" prop travles the same distance as the slower turning 27" prop it will be a quicker combination because yoiu are not loosing as much of the engines power through drag.
RossM is offline   Reply With Quote
Old 22-07-2006, 12:28 PM   #4
Registered User
 
scottyboy's Avatar
 
Country: United kingdom
Location: West Sussex
Occupation: Grease Monkey
Interests: Makin my boat faster!
Boat name: S.B Racing
Boat make: Ocke mannerfelt canopied B23 / Zapcat
Engines: Merc 200XS Gen 2 / Tohatsu 50
Cruising area: littlehampton/Southampton

Join Date: Jan 2005
Location: West Sussex
Posts: 2,652
Quote:
Originally posted by hutchy
2:1 needed when more revs needed,heavy boats or fat feckers,in boat
My bat boat isnt heavy and i aint a fat fecker! must be revs then!
__________________
Class 3C Mono EPA National speed record holder 95.35 mph Avg!
scottyboy is offline   Reply With Quote
Old 22-07-2006, 08:30 PM   #5
Registered User
 
MrRob's Avatar
 
Country: England
Location: Birmingham
Occupation: Scratching
Interests: Big Dinners
Boat name: Never Enough
Boat make: Seaquel 600xs
Engines: 225hp Merc ProMax
Cruising area: Anywhere! I prefer Weymouth

Join Date: May 2005
Location: Birmingham
Posts: 3,232
Send a message via AIM to MrRob
what prop you running scotty?
__________________
I got jumper cables!
MrRob is offline   Reply With Quote
Old 22-07-2006, 10:53 PM   #6
Registered User
 
Country: uk
Location: portsmouth
Cruising area: solent

Join Date: Oct 2005
Location: portsmouth
Posts: 290
Quote:
Originally posted by scottyboy
My bat boat isnt heavy and i aint a fat fecker! must be revs then!
i think its my nav!!!!
either that or too many magners!!!!
maybe its because i'm a pie eater?
has your bitch got a ride for little hampton yet??? or does he need some serious ballast!!
__________________
floater is offline   Reply With Quote
Old 22-07-2006, 11:19 PM   #7
hello
 

Join Date: Mar 2004
Posts: 2,739
Re: Re: 2.1 Gear Ratio

Quote:
Originally posted by PuppiesBalls
Its because there is an optimum pitch prop which I think it 27"
I thought it was less than that, around 23", but I may well be wrong.
JamesM is offline   Reply With Quote
Old 23-07-2006, 07:52 AM   #8
Registered User
 
MrRob's Avatar
 
Country: England
Location: Birmingham
Occupation: Scratching
Interests: Big Dinners
Boat name: Never Enough
Boat make: Seaquel 600xs
Engines: 225hp Merc ProMax
Cruising area: Anywhere! I prefer Weymouth

Join Date: May 2005
Location: Birmingham
Posts: 3,232
Send a message via AIM to MrRob
Re: Re: Re: 2.1 Gear Ratio

Quote:
Originally posted by Johnny Boat Dude
I thought it was less than that, around 23", but I may well be wrong.
I thought that aswel JBD. Im sure I heard Burty banging on about it and he said it was 22-24 pitch prop.
__________________
I got jumper cables!
MrRob is offline   Reply With Quote
Old 23-07-2006, 09:39 AM   #9
hello
 

Join Date: Mar 2004
Posts: 2,739
Yeah but he got it from me and I can't remember where I got it from.
JamesM is offline   Reply With Quote
Old 23-07-2006, 11:34 AM   #10
Registered User
 
scottyboy's Avatar
 
Country: United kingdom
Location: West Sussex
Occupation: Grease Monkey
Interests: Makin my boat faster!
Boat name: S.B Racing
Boat make: Ocke mannerfelt canopied B23 / Zapcat
Engines: Merc 200XS Gen 2 / Tohatsu 50
Cruising area: littlehampton/Southampton

Join Date: Jan 2005
Location: West Sussex
Posts: 2,652
Quote:
Originally posted by floater
i think its my nav!!!!
either that or too many magners!!!!
maybe its because i'm a pie eater?
has your bitch got a ride for little hampton yet??? or does he need some serious ballast!!

Believe he has a ride for L.A mate yeah! He's on he strict instruction of bend it he repairs it though! Im racin sat and then bens racing sunday! Has your naviguesser got a ride then?
__________________
Class 3C Mono EPA National speed record holder 95.35 mph Avg!
scottyboy is offline   Reply With Quote
Old 23-07-2006, 11:39 AM   #11
Registered User
 
scottyboy's Avatar
 
Country: United kingdom
Location: West Sussex
Occupation: Grease Monkey
Interests: Makin my boat faster!
Boat name: S.B Racing
Boat make: Ocke mannerfelt canopied B23 / Zapcat
Engines: Merc 200XS Gen 2 / Tohatsu 50
Cruising area: littlehampton/Southampton

Join Date: Jan 2005
Location: West Sussex
Posts: 2,652
Quote:
Originally posted by MrRob
what prop you running scotty?
Tis a secret! you have a pm matey!
__________________

__________________
Class 3C Mono EPA National speed record holder 95.35 mph Avg!
scottyboy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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


Powered by vBadvanced CMPS v3.2.3

All times are GMT +1. The time now is 03:58 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×