Marinize a Subaru?

Discussion in 'DIY Marinizing' started by curtis73, Sep 1, 2006.

  1. Inboard
    Joined: May 2012
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    Location: Johannesburg

    Inboard Junior Member

    Yes we were thinking twin blowers with a aluminum deflector
     
  2. Inboard
    Joined: May 2012
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    Location: Johannesburg

    Inboard Junior Member

    Still need to lay eyes on the diesel subaru has anyone got the specs
     
  3. originalvision
    Joined: May 2012
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    Location: Cape Coral, FL

    originalvision New Member

  4. Frosty

    Frosty Previous Member

    When water is injected in water cooled system the diam of the pipe needs to be enlarged by x 4 at least.

    You are looking a little on the small side.
     
  5. originalvision
    Joined: May 2012
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    Location: Cape Coral, FL

    originalvision New Member

    So you're saying... if my factory headpipe is 2", that it must be increased to 8"?

    You are looking a little on the large side.


     
  6. tom kane
    Joined: Nov 2003
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    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Adding water to exhaust cools hot expanded gasses so no need to increase exhaust size and a smaller exhaust diameter is easier to cool well and lag and fit. Water in any exhaust has the potential to be pushed back against the exhaust valves and even right into the motor by the pulsing of the engine and cooling contractions. (Shock waves).

    When an engine is shut down damp atmosphere in the exhaust can finish up in the cylinders particularly with some cam grinds.A dry exhaust is much better and can be cooled by adding double walls along the exhaust at hot spots.If you want a lower maintenance and reliable motor not subject to sticking valves etc.,
     
  7. Frosty

    Frosty Previous Member

    Absolutely incorrect crap. Look up marine exhaust im not doing it.

    Ille even start you off try 'Vetus exhaust' and read what is the most common mistake.

    I dont know what you mean by head pipe --you mean headers. Once water is injected you need 4 x diam. You ever see boats with 1.5inch exhaust? if you do the water will be shooting 10 feet and you will have high back pressure thats NOT needed.
     
  8. tom kane
    Joined: Nov 2003
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    Location: Hamilton.New Zealand.

    tom kane Senior Member

    www.wikipedia.org/wiki/exhaust_system

    Two-stroke engines. In a two-stroke engine a bulge in the exhaust pipe known as an expansion chamber uses the pressure of the exhaust to create a pump that squeezes more air and fuel into the cylinder during the intake stroke.this provides greater power and fuel efficiency. See Kadency effect.
    The kadency effect also applies to four stroke engines.
     
    Last edited: Jun 4, 2012
  9. Frosty

    Frosty Previous Member

    I just explained all that to you Tom on the keeping a weed eater engine quite. Glad your paying attention.

    Nothing at all to do with a marine wet exhaust though has it.
     
  10. tom kane
    Joined: Nov 2003
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    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Last edited: Jun 5, 2012
  11. tom kane
    Joined: Nov 2003
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    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Water reversion-What is it? It is simply the exhaust pulse flowing backwards momentarily during the overlap phase of the camshaft at low cycling rates.During the overlap phase, the piston is pushing out the last of the exhaust gases prior to reaching top dead center the intake and exhaust valves are still partially open.At high cycling rates the inertia of the incoming intake charge and the outgoing exhaust pulses..... Hardin Marine Cyclone (tm) Headers.
     
  12. DogCavalry
    Joined: Sep 2019
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    Location: Vancouver bc

    DogCavalry Senior Member

    That very low profile diesel could be an excellent inboard. Reduced engine box height.
     

  13. S V
    Joined: Jan 2019
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    Location: Lithuania

    S V Junior Member

    I would like put my 2 cents about marinizing Subaru Boxer diesel... I am from country, where Subaru has the one of the biggest percentage share of the cars in the world. Some years agoI think it was the first in the world with ~7% which is very good result for such a small brand. Cars are loved because of japanese reliability, good AWD/4WD system, high ground crearance, engine sound, very suitable for LPG conversion and so on. But this is for gasoline engines only, with the diesels it is exactly opposite - I know people who changed or rebuilt 2-3 engines on their 'baru spending enormous amounts of money for it.

    The engine is absolutelly worst diesel engine in decades, very close in the top of the most unreliable engines of all time near Mazda rotary and similar expensive experiments. You will have all the classic modern diesel problems with it + the bonus ones specifically for Subaru. After some model years the situation gradually got better, but the main problem persists: its design is too compact and the crankshaft cannot withstand high Nm even in partial use as in road cars. With boats it may be even worse.

    IMHO the only three situations where the conversion may be worth it:
    -you already have engine and not selling it
    -there is some packaging requirement where the opposite piston engine is the only option.
    -you are willing to invest into it constantly fixing it, reinforcing internals or just like to get your hands dirty
     
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