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Going back to NA from Turbo on CM655 Mits Diesels-gctid813151

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    Going back to NA from Turbo on CM655 Mits Diesels-gctid813151

    Okay here is a question for you all. Have any of you converted back to NA from Turbo? I am considering this due to the large cost of these obsolete engines. If somebody would post a pic of their NA it would be much appreciated also.
    Great Lakes

    The Wonder Years
    1985 3870 MY


    Please fill in your profile and signature. This helps others help you better.

    1999 3788, Cummins 270 "Freedom"
    2013 Boston Whaler 130 SS
    Anacortes, WA
    Isla Verde, PR


      My Mits are not turbo charge so I guess they are NA. What parts of the engine do you want photo's of? These engines are on a 1985 3870 twin 130's.
      Just love being on my 3870............Bill
      1985 3870
      Twin 130 Mits. not turbo charged
      Name of boat is "Plenty Of Fish"
      Live on board full time.
      North Myrtle Beach, SC


        As is often the case in boating - the simple questions can be really complicated. This is going to require some research on your part beyond the forum to get answers that fit your boat. It's not like just taking off a turbo unit and putting plugs in some holes.

        The naval architect that designed the boat used a bunch of factors to come up with the power needed to get the boat to perform. Then the numbers were run as to how to transfer that power to the water. Interpret this to mean prop design. So if you take off the turbo units and the engine turns slower your boat won't perform as well. Just as important, if you take off the turbo units and the engines produce less torque, the props can't perform either.

        If you are changing engines that's one thing - you'll play with the props anyway. If you have another goal in mind there might be serious study of the engine makers specs.


          I believe this engines came natural from the factory and this is an after market add on. so going back to na will just be making them stock. If you do remove the turbos I may be interested in purchasing them. I have kicked around the idea of adding turbos to a 1983 38XX me and my dad have.

          1994 OCEAN 48' Super Sport w/ 775hp Detroits, Hampton, VA
          1983 HATTERAS 43' DCMY w/ 410hp Detroits, Richmond, VA

          1993 4387 w/ 250 Hinos - Hampton, VA, SOLD
          1996 3388 w/ 150 Cummins - Richmond, VA, SOLD
          1989 Sea Ray 390 w/454 Mercruisers SOLD
          1983 3288 w/ 3.8 Chevy V6 gassers SOLD
          1984 3870 w/ 135 Mits SOLD