Reply
 
Thread Tools Search this Thread Display Modes
 
Old 01-07-2012, 01:33 AM   #1
Lieutenant
 
capav8r's Avatar
 
Join Date: Oct 2009
Location: Johnston, Iowa, United States
Posts: 79
Default Bravo3 4 Blade Front Prop

So, I snagged a set of B3 props on ebay for very cheap. They are the new design which is a four blade on the front and the usual 3 blade on the back. The pitch is 1 higher than my current 3x3 setup. According to Mercury's prop selector, this would be the correct pitch with the new design, 4 blade set. Here's the question: What improvements will the 4 blade make??
__________________

capav8r is offline   Reply With Quote
Old 01-07-2012, 03:23 AM   #2
Admiral

 
seapuppy's Avatar
 
Join Date: Nov 2005
Location: Everett Wa
Posts: 4,681
Default

probably more thrust which allows you to get up on plane faster.....little better effeciency on the top end.....





SP
__________________

__________________
Don't compare your life to others. You have no idea what their journey is all about.
------------------------
SSN683 Association member
Par Excellence
------------------------------
2008 Bayliner 340 - "Wild Whim"
--------------------------------------
I live in my own little world....but it's okay-they know me here!!!

Avid practitioner of the martial art: KLIK-PAO.
Tap-Rack-Bang

Anyone that sez "Size doesn't matter" has never owned a boat!
seapuppy is offline   Reply With Quote
Old 01-08-2012, 12:12 PM   #3
Commander
 
oldno7's Avatar
 
Join Date: Mar 2011
Posts: 361
Default

Found this:

In 1999, while still employed at Mercury Racing, we began development of a new set of B3 propellers. The reason we did this was Formula began mating 500 EFI engines to B3 drives on their sport cruisers. The second generation B3 props (still a 3/3 set up) was cavitation burning so fast we couldn't get 10 hours on the props before their would be a hole in the front prop blades. The new development produced 2 finalists. One set had a 4 blade front which truth be told was a mis communication accident. However, after much testing it was determined the 4/3 had the better cav. burn resistance and the performance was equally as good as the other new development set. What we found was the 3/3 original set was slightly faster still. However, the new 4/3 burned much less and had a slightly better mid range. We decided to release them under the Mercury Racing logo and it took till 2004-2005 to get it done. This is the time frame slightly after my leaving Mercury Racing. The decision to Hi Polish the props came from the management that took my place. Hi Polish looks pretty but isn't a performance related issue.

If a guy wants low end and mid range specifically, the 4/3 is the better choice. If bow lift and speed are the main concern, working the 3/3 is still the better choice. Unfortunately, I believe the 3/3 is going to go away for good.

Now, as far as the new 4/3 versus the Merc Racing 4/3, there doesn't appear to be much difference other than the finish and a bit of a geometry and cup change. Main line propellers has basically created a new propeller option to continue moving forward with new offerings in the market place. It has a duller finish and is priced to offer the consumer a option. And a Hi Polish price point to match the Racing XR version. The whole thing is kind of goofy in that main line has created a product to directly compete with the Racing product.

We have worked with the XR propellers here at BBLADES. We have yet to work with the main line 4/3.

Again, bottom line, 4/3 for low end, 3/3 for top end. Also, go down 1" of pitch if you go from the 3/3 to the 4/3.
oldno7 is offline   Reply With Quote
Old 01-09-2012, 04:00 PM   #4
Moderator

 
Join Date: Apr 2008
Posts: 3,562
Default

^^^^^^^ References/Links Please.
__________________
Leave me alone, it's Boating Season!!!
shrew is offline   Reply With Quote
Old 01-10-2012, 02:29 AM   #5
Commander
 
oldno7's Avatar
 
Join Date: Mar 2011
Posts: 361
Default

Shrew

Came from here:


http://midwestboatparty.com/forum/ar...p/t-20568.html
oldno7 is offline   Reply With Quote
Old 04-16-2012, 01:36 AM   #6
Lieutenant
 
capav8r's Avatar
 
Join Date: Oct 2009
Location: Johnston, Iowa, United States
Posts: 79
Default

Launched the boat yesterday with the 4x3 propset. WOW!! It comes on plane much quicker AND I am showing 2~3 higher mph. Another positive, in another thread I had asked about a vibration when the drive was trimmed up much at all. That vibration/noise is gone with the new propset. I am guessing the 3x3 props were cavitating? Here is a really odd thing: The set I had (which was the factory setup) is a 20p. This new set is a 22 1/2p. I am still hitting right at if not slightly over 5k rpm's. Apparently I was under propped with the factory supplied props.... Anyway, I think I have found the right props for my boat!!
capav8r is offline   Reply With Quote
Old 04-16-2012, 01:09 PM   #7
Admiral

 
ss3964spd's Avatar
 
Join Date: Jul 2009
Location: Fairfax Va
Posts: 1,512
Send a message via Yahoo to ss3964spd
Default

ss3964spd is offline   Reply With Quote
Old 04-16-2012, 02:49 PM   #8
Lt. JG
 
Join Date: Mar 2012
Location: Maryland
Posts: 29
Default

Quote:
Originally Posted by capav8r View Post
Anyway, I think I have found the right props for my boat!!

What boat do you have Cap?
rcswando is offline   Reply With Quote
Old 04-16-2012, 05:50 PM   #9
Lieutenant
 
capav8r's Avatar
 
Join Date: Oct 2009
Location: Johnston, Iowa, United States
Posts: 79
Default

It is an '06 2600SE, 350 Mag/MPI
capav8r is offline   Reply With Quote
Old 04-20-2012, 04:49 PM   #10
Lt. Commander

 
Join Date: Feb 2010
Location: Half Moon Bay, CA
Posts: 152
Default

Cap:
You may remember we have the same boat, although my engine is a 5.0L MPI. The performance improvement is great news, and looks like something I need to consider. I never would have thought of even looking at Ebay for props. Were the props new or used? Would you mind passing along the price you paid?

Also, when you say you're showing 2-3 higher mph, are you talking about top speed? Or do you mean fuel efficiency (gph)?

Great to hear your boat is performing so well and you're back on the water!

Tom
__________________

__________________
2006 Maxum 2600SE with Mercruiser 5.0L MPI and BIII Drive
iceman is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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. The time now is 10:31 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.