Like Tree0Likes

1.5 or 1.35 gear ratio?

Reply
Old 01-08-2008, 07:54 PM
  #1
VIP Member
VIP Member
Thread Starter
 
PARADOX's Avatar
 
Join Date: Dec 2005
Location: Florida
My Boats: Formula 272 Sold, 26 Infinity, 4 sale, 08-33' Avanti 4SALE
Posts: 2,697
Default 1.5 or 1.35 gear ratio?

Boat:33', 7200 pounds, Std. "V" no steps. 24* deadrise.
Motors, twin 525's.
Bravo. XR.
Gear ratio???/

Since I have a choice, what's the better gear ratio? and why?

Thx

P
PARADOX is offline  
Reply With Quote
Old 01-08-2008, 08:29 PM
  #2
Registered
 
MitchStellin's Avatar
 
Join Date: Nov 2000
Location: Grand Haven, MI USA
My Boats: Zodiac RIB
Posts: 3,124
Default

The 135 stronger and can spin a smaller prop. I had them in an AT, a 32, and I never had a problem. I heard they were stronger and I could have gone down to a 21 but ran a 23. My understanding is that it was a better drive set up.
MitchStellin is offline  
Reply With Quote
Old 01-08-2008, 09:53 PM
  #3
Registered
 
Join Date: Jul 2007
Location: Austin,Texas
Posts: 2,111
Default

1.50 It will have better acceleration. More reduction may be even better.
MOBILEMERCMAN is offline  
Reply With Quote
Old 01-09-2008, 01:18 AM
  #4
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha
My Boats: .......32............. ...............Active Thunder....
Posts: 15,754
Default

You will probably be in the range of a 30-32 pitch Bravo prop with a 1.5 ratio. You don't want to go higher than 32 with bravo props.

I would go with 1.35's and run something in the 28 pitch range. You will still have plenty of acceleration with your power. I have 1.36's/24" props behind 502mpi's and have no issues. The boat accelerates fine. Never had 1.50's on it to make a comparison though.
Griff is offline  
Reply With Quote
Old 01-09-2008, 10:07 PM
  #5
Registered
 
Join Date: Jan 2008
Posts: 2
Default contact

PARADOX please pm me
llwleo is offline  
Reply With Quote
Old 01-09-2008, 10:29 PM
  #6
Registered
Platinum Member
 
Join Date: Sep 2001
Location: Kingsville----lake erie
My Boats: 97 41' Saber --Ancestral Spirit
Posts: 1,328
Default

I'm sorry; am I missing something?? the Avanti hull is very much like a cigarette hull? No?
Would the 28' Apache hull be much different let alone the 30' Bullet? If so how can you swing a 32 pitch Bravo with 525's??

I am in the middle of this very same question 1.35 or 1.50 ratio and have run the numbers on M Bam caculators backwards and forwards and don't see how anything other than a 1.5 will work.

Please someone show me what I'm missing
delsol is offline  
Reply With Quote
Old 01-09-2008, 10:58 PM
  #7
VIP Member
VIP Member
Thread Starter
 
PARADOX's Avatar
 
Join Date: Dec 2005
Location: Florida
My Boats: Formula 272 Sold, 26 Infinity, 4 sale, 08-33' Avanti 4SALE
Posts: 2,697
Default

I doubt I can run a 30"- 32" prop with 525's and 33' "V" hull to, but as far as the ratio, I am not certain which wat would be better. I guess I rather have speed and acceleration. The boat panes pretty good.

llwleo.. I can't PM you. I don't think you have that option. E-mail me at [email protected]
PARADOX is offline  
Reply With Quote
Old 01-09-2008, 11:35 PM
  #8
Registered
 
Back4More's Avatar
 
Join Date: Feb 2002
Location: Lake Michigan
My Boats: 353 Fastech
Posts: 6,624
Default

Go with the 1.50...alot cheaper

Last edited by Back4More; 01-09-2008 at 11:43 PM.
Back4More is offline  
Reply With Quote
Old 01-09-2008, 11:40 PM
  #9
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha
My Boats: .......32............. ...............Active Thunder....
Posts: 15,754
Default

Its only 7200 lbs. 32 AT's run 28's or labbed 30's with 500's and weigh about the same.
Griff is offline  
Reply With Quote
Old 01-09-2008, 11:57 PM
  #10
Registered
 
Back4More's Avatar
 
Join Date: Feb 2002
Location: Lake Michigan
My Boats: 353 Fastech
Posts: 6,624
Default

I agree.
With 28-30's it will run at about 80mph.
Back4More is offline  
Reply With Quote
Reply

Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
saulesses
Prop Talk
1
06-13-2007 10:12 PM
saulesses
Prop Talk
0
06-12-2007 12:01 AM
docmanrich37
General Q & A
0
04-10-2006 07:21 AM
Swede
General Q & A
1
02-27-2004 04:21 PM
EliminatorBill
General Q & A
2
02-05-2003 08:45 PM



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 On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 10:25 AM.


Copyright 2011 OffShoreOnly. All rights reserved.