repower question...

Discussion in 'Diesel Engines' started by firepiper, Aug 15, 2006.

  1. firepiper
    Joined: Aug 2006
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    Location: Plymouth, Ma

    firepiper Junior Member

    Hello, I found a really nice deal on a running pair of takeout Volvo TAMD41's (200 hp). I'm wondering if they would be enough to repower a 35 luhrs (downeastern design) Alura. 12600 lbs. It originally had twin small block chevy's. The horsepower is less, but, will the torque be better? I don't mind going a little slower, I realyywant more effieciency. Any thoughts? Mark
     
  2. bilgeboy
    Joined: Dec 2005
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    Location: Boston

    bilgeboy Senior Member

    That should be plenty of power. The torque is definately way better with diesels. I've got twin 135's in a 32' bayliner (Newer models are called 35' with integral bow pulpit and swimplatform). I love the efficiency. I can cruise for days at hull speeds, now getting an easy 16 knots at WOT on calm seas.

    You will need to reprop, and I'm sure someone here can help with those calculations. I wouldn't sweat the speed calculations, just figure out what transmission ratios and prop diameter and pitch will make sense with those engines on that hull. If you can get a good deal on the engines, grab 'em. Diesels rock.

    I would love to follow the installations (might even be able to offer some helpful advice) if you will continue to post the project here.

    Go for it, and good luck!

    Mike
     
  3. alex fletcher
    Joined: Jun 2006
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    Location: Ettalong Beach NSW Aust.

    alex fletcher Junior Member

    lovely thay will do a great job we have fitted a number to a number of vessels you will not lose speed at all u should gain speed a little and the boat will come out of the hole faster. you will need the services of a Prop scan franchise to get the best results of course, as your porps have to be just right you need the science
     
  4. rpeter46
    Joined: Oct 2006
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    Location: MI

    rpeter46 New Member

    1969 Formula

    Can you send me a couple pics of your 1969 Formula? I recently bought a "1973" Formula Thunderbird and I'm getting the feeling that the information on the title is wrong. Can you also tell me where to find the HIN on that boat? Thanks, I really appreciate it!
     
  5. firepiper
    Joined: Aug 2006
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    Location: Plymouth, Ma

    firepiper Junior Member

    I'm not positive, but, I don' believe there were hin's back then. Mine did not have one.
     
  6. rpeter46
    Joined: Oct 2006
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    Location: MI

    rpeter46 New Member

    1969 Formula

    Thanks for the HIN info. Can you help me out with some pics?
     
  7. StianM
    Joined: May 2006
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    Location: Norway

    StianM Senior Member

    Torque don't mather.

    it's the power at diferent revs.

    The Diesel has the power spread over a larger area off the RPM curve so you should experience faster aceleration at low revs and speed's.

    You should get out off the water a lot quicker.
     
  8. fish1860
    Joined: Mar 2007
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    Location: Jensen Beach, FL

    fish1860 New Member

    Firepiper. I am currently looking at purchasing a 1988 Alura 35. with 454's
    I addition to a marine survey can you give me some insite on what to look for or what to out for before I get this. Any help would be greatly appreciated.
     

  9. Karl2
    Joined: Feb 2005
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    Location: Right Coast

    Karl2 Junior Member

    TAMD41 in 35' Luhrs

    Should work very well - You should loose some speed but be able to cruise the same and for less fuel.

    A couple of things to consider with the 41's: Make sure you run a 2:1 gear ratio (If they come with Volvo gears it will be 1,9x:1 and that is fine) and go for 18-19" diameter wheels. Avoid 1.5:1 gear ratios - Will not work well with these motors in this boat.

    Karl
     
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