1980 23.6 Mako Prop size info

Discussion in 'Inboards' started by Ballshak31, Jun 10, 2008.

  1. Ballshak31
    Joined: Jun 2008
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: nc

    Ballshak31 New Member

    Heavey boat. I have a 1980 Mako 23.6 inboard 350 Crusader 260 hp. velt 1.88 to 1. weight 4000 plus some ?
    recommended wot tac 4000 to 4400. present prop 16x16 3 blade top rpm 4700 speed 23 mph. plains good but looking better cruise speed and fuel consumption. any suggestion?? thks
     
    Ballshak31, Jun 10, 2008
    #1
  2. Jango
    Joined: Aug 2005
    Posts: 519
    Likes: 7, Points: 0, Legacy Rep: 63
    Location: Mid Atlantic

    Jango Senior Enthusiast

    16 x 16, 3 blade is too small. You're getting alot of slippage.

    Using 4800 LB total weight with Driver and minimum fuel, calculations show a 18 x 18, 3 blade (.55 D.A.R. min.) or if you don,t have space a 17 x 18, 4 Blade (.63 D.A.R. min). Drive ratio 1.88 to 1

    With 260 HP, you should get 35 MPH @ 4400 rpm.
    RPM @ cruise will be reduced and fuel consumtion should be noticeably less.

    Keep in mind, the above numbers are only correct for 260 HP and 4800 lb total weight. If your minimum total weight is higher, Pitch will be less and perhaps Dia larger.
     
    Jango, Jun 10, 2008
    #2
  3. Ballshak31
    Joined: Jun 2008
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: nc

    Ballshak31 New Member

    In the Know Thks

    I sorta felt "small" was the word.... It was nice to hear from some is "IN THE KNOW". Glade i registered!!! Thks Bob in;) East Coast NC!
    Jango...18x21 4 blade too much right?
     
    Last edited: Jun 10, 2008
    Ballshak31, Jun 10, 2008
    #3

  5. Jango
    Joined: Aug 2005
    Posts: 519
    Likes: 7, Points: 0, Legacy Rep: 63
    Location: Mid Atlantic

    Jango Senior Enthusiast

    WAY TOO MUCH, you'll bog the Engine down.

    18x21 4 blade would be OK for a 360 HP Big Block or diesel.
     
    Last edited: Jun 11, 2008
    Jango, Jun 10, 2008
    #4
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.