Go Back  Offshoreonly.com > Owners Forum > Magnum Marine
Prop rotation on 27 Sport >

Prop rotation on 27 Sport

Notices

Prop rotation on 27 Sport

Thread Tools
 
Old 10-11-2015 | 01:25 PM
  #1  
Thread Starter
Registered
10 Year Member
 
Joined: Sep 2013
Posts: 86
Likes: 3
Default Prop rotation on 27 Sport

I'm wondering what rotation you guys are running? In the past we ran the props inward, or left hand rotation on the Starboard drive. I've noticed however, that on most of the pics I've seen lately they are turning them outward. What your thoughts on this?
Mine has Merc. 280TRS with 21p Mirage turning inwards.

Einar
viking60 is offline  
Reply
Old 10-11-2015 | 02:32 PM
  #2  
Registered
15 Year Member
 
Joined: Apr 2007
Posts: 417
Likes: 2
Default

I have always turned the props outwards to lift the stern.

With my Bravo 1`s at 5700 rpm 26" pitch circa 71/72 mph

However I have never turned them inwards so I to will be interested to read the responses which you receive.

Kalaazar
Kalaazar is offline  
Reply
Old 10-11-2015 | 10:52 PM
  #3  
h2oboater's Avatar
Gold Member
20 Year Member
Gold Member
 
Joined: Dec 2003
Posts: 3,496
Likes: 63
From: NewBaltimore Mi
Default

Originally Posted by viking60
I'm wondering what rotation you guys are running? In the past we ran the props inward, or left hand rotation on the Starboard drive. I've noticed however, that on most of the pics I've seen lately they are turning them outward. What your thoughts on this?
Mine has Merc. 280TRS with 21p Mirage turning inwards.

Einar
Short Circuit is one of the best running & dialed in Sports & it turns it's props outward.. My old Trs race Mag turned them outward as well as my Volvo sport I have now.
h2oboater is offline  
Reply
Old 10-12-2015 | 01:54 PM
  #4  
Thread Starter
Registered
10 Year Member
 
Joined: Sep 2013
Posts: 86
Likes: 3
Default

Thanks guys.
I can't wait to try it outwards. Do you think there will be a noticeable difference in
top speed or handling?

Einar
viking60 is offline  
Reply
Old 10-12-2015 | 03:16 PM
  #5  
Registered
15 Year Member
 
Joined: Apr 2007
Posts: 417
Likes: 2
Default

Hi Einar,
We have just completed a weekend of propeller trials with some surprising results.
Best overall performance 14" x 26" 3 blade over hub cleavers 71 mph at 5800 rpm, neutral lift
15" x 26" 4 blade over hub cleavers 68 mph at 5100 rpm, neutral lift
14.75" x 25" 4 blade through hub Hydromotive 68 mph at 5000 rpm big stern lift
Bravo 1 24" 4 blade through hub 69 at 5600 rpm with good bow lift.
Mirage Plus 25" pitch 3 blade through hub 75 mph at 5100 rpm ( But a real pain to get onto the plane) good overall trim and lift.
So whether the props turn in or out, through hub, over hub cleaver or what ever is down to drive height, boat weight, engine powerboat, angle of trim and what is you want out of it for your use.
PS my target is a do it all set of props good for 75mph at around 55/5600 rpm and have not found them yet, but I am still looking.
Kalaazar
Kalaazar is offline  
Reply
Old 10-12-2015 | 03:33 PM
  #6  
CIG3's Avatar
Registered
25 Year Member
 
Joined: Jan 2001
Posts: 2,292
Likes: 20
From: Grand River, Ohio
Default

My 28 Cigarette loved the Hydromotive Intimidator III. I believe they were 23 pitch. They run nice and neutral but will carry the nose with a little trim. Not a big fan of a 4 blade on this hull design unless you are running a high "X" (17"-17.5")
CIG3 is offline  
Reply
Old 10-13-2015 | 02:18 PM
  #7  
Registered
15 Year Member
 
Joined: Apr 2007
Posts: 417
Likes: 2
Default

Originally Posted by CIG3
My 28 Cigarette loved the Hydromotive Intimidator III. I believe they were 23 pitch. They run nice and neutral but will carry the nose with a little trim. Not a big fan of a 4 blade on this hull design unless you are running a high "X" (17"-17.5")
Thank you for your input, interesting.
Kalaazar is offline  
Reply
Old 10-13-2015 | 06:24 PM
  #8  
Thread Starter
Registered
10 Year Member
 
Joined: Sep 2013
Posts: 86
Likes: 3
Default

Thanks guy's for the info, but how about rotation? Was there any rotation changing done with all of the prop testing?

Einar
viking60 is offline  
Reply
Old 10-13-2015 | 08:13 PM
  #9  
Registered
 
Joined: Mar 2006
Posts: 673
Likes: 12
Default

-----Like Mark (the crew chief) said,,,Twist em outwards!!! Works for Short Circuit and she is just about the best handling fast boat I have ever had the pleasure of driving........Bill S
olredalert is offline  
Reply
Old 10-14-2015 | 02:25 AM
  #10  
Registered
15 Year Member
 
Joined: Apr 2007
Posts: 417
Likes: 2
Default

No we never turned the propellers inboard because we wanted direct comparisons with the same rotation.

However what did become apparent is for a better top speed a little stern lift was needed and it is my understanding the this is more achievable with the propellers turning outboard rather than inboard as the latter tends to create a "hole" to drop the stern into.

Kalaazar
Kalaazar is offline  
Reply


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

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.