Formula 330 SS outboard conversion

Discussion in 'Boat Design' started by jackazz99, Apr 9, 2015.

  1. jackazz99
    Joined: Apr 2015
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: HK

    jackazz99 New Member

    I have been offered a Formula 330 SS with damaged engines.
    All else on boat is in good condition.
    Am contemplating converting the boat to twin 250 outboards , would the hull / transom of this boat be an eligible candidate for such a conversion ?
    I have 2 yamaha 250's that came of a previous boat so depending on the installation cost of a bracket , it could be an interesting option.

    Any feedback appreciated.
  2. Mr Efficiency
    Joined: Oct 2010
    Posts: 10,401
    Likes: 1,036, Points: 113, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    Have you thought what effect might come with lifting a lot of weight out of it ? It won't sit in the water the same as previously.
  3. jackazz99
    Joined: Apr 2015
    Posts: 2
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: HK

    jackazz99 New Member

    Sure , the weight of the inboards are much heavier then the 2 x 250 outboard , but this could be compensated with additional weight such as water or additional fuel tank I reckon.
  4. daysgoneby
    Joined: Jun 2014
    Posts: 4
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Canada

    daysgoneby New Member

    That's a nice boat, I'd just replace the stern drives and be done with it, unless you do a really good job with the outboards resale would be hurt.

  5. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 494, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Typically stern drive transoms aren't built as stout as outboard versions, so you'll need to investigate this. 500 HP in outboards, hanging on the transom or on a bracket will surely move the CG and trim considerably, so besides transom reinforcement, possibly bracket considerations, you'll need to move things around. It's not just the comparative weights, but their locations. This isn't complicated, though should be well executed.

    In the end, it'll likely be less costly by simply dropping some crate engines in place and getting back on the wet stuff. No reinforcements, no brackets, no moving tanks, batteries, adapting, cutting and adjusting steering, controls, etc., just transplant and go. Besides a couple of small blocks are cheap, especially if you're willing to do a lot of the work (long blocks).
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.