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45’-60’ 2015 or newer Shaft Drive yacht recommendations

Discussion in 'General Yachting Discussion' started by DavieJ, Nov 26, 2022.

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  1. DavieJ

    DavieJ New Member

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    I’m back. As it turns out, pod drives are not what I should be buying, despite the fact that manufacturers are putting them in literally everything. I’m not even sure if the Cummins/Zeus combo is even being sold anymore.
    What are the recommended manufacturers who have stayed away from pod drives and are making the good, old shaft drives for propulsion?
    I’m new and really don’t know what to look for besides YachtWorld then clicking on the propulsion tab to get the info.
    Thanks all. I appreciate the advice
  2. ranger58sb

    ranger58sb Senior member

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    You might find the Powerboat Guide useful. The softcopy version is keyword-searchable...

    -Chris
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  3. DavieJ

    DavieJ New Member

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    Chris. I downloaded the guide. Not searchable on my phone. I’ll try on my computer. Useful info for sure but I don’t think I can narrow my search criteria like I’d want. Thanks tho.
  4. Fiammetta42

    Fiammetta42 Member

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    Look @ Ferretti group boats in your preferred size range .
    Plenty of choices of straight simple reliable shafts .
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  5. gr8trn

    gr8trn Senior Member

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    Search radius?
    New or only previously owned?
    Budget?
    Cruising grounds?
    Galley up or down?

    I have 2009 Zeus hooked to Cummins. I have had no issues, I am on schedule with maintenance and seals but my next boat will be shaft. I like the set up, the use, pretty shallow draft, but I am concerned that aging Zeus pods may be a resale liability.

    I have noted, as you have, this size boat is almost always VP IPS:(

    The Prestige line does offer shaft v drive in some of their lineup so don’t give up on that option.
  6. Capt J

    Capt J Senior Member

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    55' Princess, Sunseeker 52' or 55', 60' Hatteras to name a few. You'll get 30% better fuel economy on a pod boat and a lot more interior volume IF the builder took advantage of it.
  7. cleanslate

    cleanslate Senior Member

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    What’s the reason for better fuel economy? Why ?
  8. bernd1972

    bernd1972 Senior Member

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    Better fuel economy is related to several aspects: Drives produce their thrust horizontally, no rudders aft of the props, less stuff in the way of water towards the props, counter-rotating pair of props on the pods (therefor less losses of efficiency due to less to no rotation in the flow of water behind the pods).
  9. Capt J

    Capt J Senior Member

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    The straight thrust angle from them, drag, etc. Generally a 450hp POD is equivalent to around a 600HP straight inboard.
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  10. cleanslate

    cleanslate Senior Member

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    How about that…that is a lot of Hp difference.
  11. Liam

    Liam Senior Member

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    Its a big misguided this number as used here and in marketing schemes by Volvo.
    It is possible but for that to happen the IPS boat will need to have a very flat Vee buttom and hull designed for the propulsion from fore to aft.
    Which if you do the same for a shaft boat the difference will in the region of 5%.

    So like with like you are looking at 10% real gain with an IPS boat in fuel economy so speed gains.
  12. gr8trn

    gr8trn Senior Member

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    Very flat V bottom? Can you describe a model or some degrees of V you are referring to?
  13. Liam

    Liam Senior Member

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    The preferred angle for an IPS boat is about 12/13 degrees deadrise (medium Vee) closing aft. But what is important is also to forward of the IPS pod to about three meters (ten feet) it is suggested you do not go more then twenty degrees.
    While twelve degrees closing aft is no deal, many sportfish as Hatteras and Viking always close in these numbers, they tend to be pretty deep further and you can throw many rough seas to them.
    But with IPS boats you will see that many tend to also rather flat Vee even forward. Possibly the only exception being triple IPS boats like the Azimut S series.
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  14. AMG

    AMG YF Moderator

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    In my IPS installation guide from Volvo Penta they say from 13-24 degrees deadrise...
  15. cleanslate

    cleanslate Senior Member

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    Interesting stuff...but I will always take the shaft....drive boat that is. It's stuff I know and can work on myself. Dealers of any kind and Cleanslate don't mix. ;)
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  16. mapism

    mapism Senior Member

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    Does it say this? If so, It seems to me that they don't put their money where their mouth is.
    Aside from being personally aware of builders who were strongly recommended by VP engineers to keep any hull meant for IPS installation nowhere near 15 deg at most, VP must have suggested also at Delta to NOT follow their own installation guides, if you check out this photo.
    As you know much better than myself, the hull area where the pods are installed (which is what really matters, more that the closing aft deadrise) is practically flat.
    Even just based on the photo, I'm sure to exaggerate if I say that the pods are outward angled at 4 or 5 degrees, if that.
    And rightly so, mind: I'm not saying that Delta made a mistake - if anything, it's the installation guide that you mention which is laughable.
    Make the pods rotate along a 24 deg axis, and when hard steering at speed any boat would risk to capsize, courtesy of the listing moment introduced by the pods thrust! :confused:
    [​IMG]
    Last edited: Nov 30, 2022
  17. AMG

    AMG YF Moderator

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    My installation guidebook is not new, so they may have changed this today, I don't know. But we had a hard time to get our hull accepted by VP, probably because it would also work well with Zeus at the time... And yes, the drives are in a 5 degree angle.

    But again, this is not what VP recommended and not what most other brands are doing, most of them are using their existing hulls without modifications for IPS and most of these are getting a lot better performance figures than with straight shafts...

    In Swedish.. ;-)

    IPS Installation.jpg
  18. Capt J

    Capt J Senior Member

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    The closest head to head comparison I know of, is the 40' Cabo, with 600HP zues it was 1 knot faster at cruise and WOT than 800hp MAN's and shafts. 45 gph versus 62 gph at cruise.
  19. mapism

    mapism Senior Member

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    Do they use two completely different moulds for those Cabos?
    That's the point with pods, a hull can be either optimized for them or for shafts, but never for both.
    And I'm not talking of the pod placement alone, which is obviously different - it's the whole hull profile that is "either or".
    On top of that, the choice affects also weight distribution/balance.
    True, several builders (possibly Cabo included, I'm not sure - hence the question) use the same hull for both propulsions, for obvious cost reasons.
    But this implies that only one of the two is the "right" boat, by definition, so to speak. Or are both "wrong", which is also a possibility!

    In fact, weird as it may sound, the best comparison is NOT between two identical boats, but between two different boats, as long as the type/size/displacement is close enough.
    The key factor is that each must come from a builder focused either on pods or shafts, without giving the choice between both.
    Which is always a commercial/marketing choice, not a sound technical one.
    In fact, that's the route taken for instance by Sunseeker (which is among the most marketing-oriented builders) for their smaller boats...
  20. Capt J

    Capt J Senior Member

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    The 40' Cabo's ride the same with pods or shafts. The hull was modified where the pods are mounted I believe. I think the comparison on the same boat is the most accurate. The Zues boat with 600hp diesels is 1 knot faster than the MAN boat with 800 HP diesels.......45 GPH versus 62 GPH at same cruise speec (within a knot) is pretty impressive.

    It's like the only direct comparison of Arnesons versus Jets I know of is that 68' Azimut built.

    2 different boats can perform TOTALLY differently even same size/type/displacement due to hull design. Some are simply much faster (and efficient) than others with the same power.
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