Go Back  Offshoreonly.com > General Discussion > General Boating Discussion
What pitch props get the best fuel economy (?) 38ft Scarab Twin 502's Bravo I's >

What pitch props get the best fuel economy (?) 38ft Scarab Twin 502's Bravo I's

Notices

What pitch props get the best fuel economy (?) 38ft Scarab Twin 502's Bravo I's

Old 09-20-2012, 10:39 PM
  #1  
Registered
Thread Starter
 
Join Date: Jun 2010
Location: Offshore, Thailand
Posts: 56
Likes: 0
Received 0 Likes on 0 Posts
Default What pitch props get the best fuel economy (?) 38ft Scarab Twin 502's Bravo I's

Once again I am asking for more advice from you avid boaters.

I am not the rocket scientist about props - what pitch prop gives me the best fuel economy ? [ 38ft Scarab Twin 502's Bravo I's ]

What is the differences for props in general ?

This is my first boat of this size and want to make the right choices.
siamjimi is offline  
Old 09-20-2012, 10:41 PM
  #2  
Registered
Thread Starter
 
Join Date: Jun 2010
Location: Offshore, Thailand
Posts: 56
Likes: 0
Received 0 Likes on 0 Posts
Default

FYI - I am running long distances in this Scarab
siamjimi is offline  
Old 09-20-2012, 11:07 PM
  #3  
Registered
iTrader: (1)
 
Join Date: Aug 2004
Location: Baton Rouge La.
Posts: 2,297
Likes: 0
Received 0 Likes on 0 Posts
Default

What are You running now. An what rpms. what kind of load? That is a loaded question. I will guess. 3800 4 blade. You asked for long dist. Lots of pitch if your not goiing through lot of idel no wakes. Artie
akaboatman is offline  
Old 09-20-2012, 11:43 PM
  #4  
Registered
Thread Starter
 
Join Date: Jun 2010
Location: Offshore, Thailand
Posts: 56
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by akaboatman
What are You running now. An what rpms. what kind of load? That is a loaded question. I will guess. 3800 4 blade. You asked for long dist. Lots of pitch if your not goiing through lot of idel no wakes. Artie
Thank you Artie [akaboatman];

WHAT I HAVE NOW - I have no idea what i have now - I have yet to put this boat in the water (been repairing the motors) and the props are in the storage compartment inside the cabin. I can ask the boat specialist working on my boat what i have.

My idea was to use the props i have as spares and buy myself a set of fuel economy props. I am shipping this boat to SE Asia and require a set of spares in the event I hit something and knock a chunk out of one of them - there are no prop shops in the areas i will frequent - all props would have to come from USA as far as i am concerned.

RPM's - ? - I will be getting a feel for the most economical rpm's once I get this boat into the water - I am thinking and have been told around 3,300- / 3,500- (?) is good for these 502's.

LOAD - I am dangerously assuming I will have around 11,000 lbs total weight when I am fully loaded with fuel, passengers, general items - the boat is 9,600 lbs dry.

SEA-CONDITIONS/WAKES - I am running offshore for long distances in varying sea conditions - preferably smooth to slightly choppy in the Gulf Of Thailand [GOT].

QUICK CONNECT / DISCONNECT (?) - Also - if you or anyone can explain the quick connect / disconnect types or prop nuts available - I need to remove them each time I put the boat into storage. I have heard there are a few different makes and styles - some being better than others.
siamjimi is offline  
Old 09-21-2012, 12:31 AM
  #5  
Fast Singles Club
Gold Member
iTrader: (8)
 
the deep's Avatar
 
Join Date: Oct 2011
Location: Raystown Lake , Pa.
Posts: 3,979
Received 386 Likes on 155 Posts
Default

Thaistick ? Anyway brother Siam , prop your boat to run at the middle of your wide open throttle R.P.M.'s . For your 502's it is probably 4800 to 5200 . So if you prop it to run at 5000 wide open that will give you a nice efficient cruise speed at say 3300 . May i suggest Bravo 1 four blade props for a good bite on the water .
the deep is offline  
Old 09-21-2012, 01:05 AM
  #6  
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha/LOTO
Posts: 19,545
Received 1,810 Likes on 900 Posts
Default

Just run the props you have and see how they work before you worry about buying new ones. I hope you realize that you will most likely be getting about 1 mile per gallon of fuel at cruise speeds.
Griff is offline  
Old 09-21-2012, 01:57 AM
  #7  
Registered
iTrader: (2)
 
Join Date: Aug 2005
Location: Between A Womans Leggs in IL
Posts: 6,306
Likes: 0
Received 1 Like on 1 Post
Default

hands down a 5 blade maximus will be the best prop for mpg..a friend use's 1/3rd less fuel in his foemuls compared to his bravo one 4 blades..as for quick change prop doohickys,,no such thing..just make sure you get some drive locks and prop locks from mcguard..
FIXX is offline  
Old 09-21-2012, 07:09 AM
  #8  
Registered
iTrader: (2)
 
Join Date: Mar 2002
Location: Miami Beach
Posts: 2,142
Received 3 Likes on 2 Posts
Default

I have tried the maximus VS Bravo on two boats now and the bravo was better for mpg in both cases. The maximus grip the water much better than the bravo so you would have to try them and see. On the 28 daytona a hydromotive p5x was the best prop, I tested a lot of props 10+ On my current boat a 26 bravo has been the best overall and also for mpg, and I have tried everything from 27 mirages to 28 p5 hydromotives. On my current boat the 24 maximus was about .2 mpg worse than the 26 bravo, except when fully loaded with fuel, gear and 10 people then they were the same.

Unfortunately for you the reality is you have no knowledge of your boat how it runs and what the normal mpg is, and I am also assuming since they are 502's that you don't have fuel flow sensors installed so it is going to be hard to compare one prop to another. Ideally a 5 blade should be the best but in reality every boat is different and the only way to find the best prop is to try them out. I would start with a stock bravo 24p and use that as a baseline to compare against.

also never seen or heard of a quick connect for prop nuts
pstorti is offline  

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


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.