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  • #16
    Originally posted by Scott Danforth View Post
    with the drive off, you have half the work to pull the motor done. disconnect the cables, exhaust, fuel lines, remove the front motor mount bolts and transom shield bolts and lift the motor out. maybe a 30 minute process

    any 1986-1995 5.7 from a truck out of a pull-a-part salvage yard would work. just change the core plugs for brass, and use marine head gaskets. you can be back on the water for under $500

    or have your motor rebuilt and be back on the water for about $1700
    what do you think could be brokem? rod bearing or something?

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    • #17
      without pulling it apart, its a guess

      could be valve train, could be broken piston, could be bearings.

      either way, your motor is coming out.
      Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

      1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

      Past Boats
      1970 Wooster Hellion - Merc 9.8
      2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
      1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

      What’s behind you doesn’t matter.Enzo Ferrari

      Comment


      • #18
        Originally posted by Scott Danforth View Post
        without pulling it apart, its a guess

        could be valve train, could be broken piston, could be bearings.

        either way, your motor is coming out.
        what do you think about something like this? ill keep the truck block in mind, i dont think i want to rebuild the current one. its was a jasper rebuilt in 2012 and its already needing another. on this new half package though from michigan motorz what do you think? currently the onlly brand new parts on current engine are the fuel pump risers manifold and starter. which it looks like i could use those on this.

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        • #19
          These are just a few of the features that add up to more horsepower, greater low end torque, excellent durability, and longevity. 100% of your wakeboard and ski boats such as Ski Nautique, Malibu, Mastercraft, Tige, Supra, Moomba, etc use this exact 5.7L Vortec engine.

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          • #20
            You can build a brand new stroker motor for $4200. However its your money
            Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

            1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

            Past Boats
            1970 Wooster Hellion - Merc 9.8
            2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
            1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

            What’s behind you doesn’t matter.Enzo Ferrari

            Comment


            • #21
              Originally posted by Scott Danforth View Post
              You can build a brand new stroker motor for $4200. However its your money
              i just mainly want something reliable and i dont personally build any of the engine or have tools to install it. i can put on the manifolds and other minor parts no problem, thats why i was considering the silver package from Michigan motorz. whats the deal with building a stroker engine vs just having this one shipped in the have the mechanic drop it in? if i decided to do the stroker what conversions would i need with my current 87 5.7 omc setup or do all parts just transfer and engine drops in and go? what brand of engine should i be looking at as well?
              Last edited by cowlotter; October 9th, 2019, 12:25 PM.

              Comment


              • #22
                starting from scratch and buying new parts, a 5.7 and 6.2 are the exact same cost. the dimensions of the engines are the exact same.

                your dealing with a small block chevy with OMC stuff bolted to it. your replacement motor will be a SBC with your existing OMC stuff bolted to it.

                not sure by what you mean brand..... because the brand is General Motors, and you are dealing with the corporate marine motor which is a SBC.

                the 315 hp is the flywheel hp for a 260hp motor/drive package

                going to a vortec motor is vortec heads and a roller crank.

                reliability is purely a function of maintenance.
                Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

                1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

                Past Boats
                1970 Wooster Hellion - Merc 9.8
                2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
                1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                What’s behind you doesn’t matter.Enzo Ferrari

                Comment


                • #23
                  Originally posted by Scott Danforth View Post
                  starting from scratch and buying new parts, a 5.7 and 6.2 are the exact same cost. the dimensions of the engines are the exact same.

                  your dealing with a small block chevy with OMC stuff bolted to it. your replacement motor will be a SBC with your existing OMC stuff bolted to it.

                  not sure by what you mean brand..... because the brand is General Motors, and you are dealing with the corporate marine motor which is a SBC.

                  the 315 hp is the flywheel hp for a 260hp motor/drive package

                  going to a vortec motor is vortec heads and a roller crank.

                  reliability is purely a function of maintenance.
                  basically by brand i mean who would i buy a new 6.3 383 stroker from thats marine rated and a direct replacement for the 87 omc. i see a couple remaned ones on ebay linked here, what do you think.

                  1 - https://www.ebay.com/itm/Reman-6-2L-...OIAAOSwqVBZZNY D

                  2 - https://www.ebay.com/itm/383CI-Strok...kAAOSwrXVde5pY

                  3 - https://www.ebay.com/itm/ATK-Chevy-3...wAAOSwKt5ZlxGq

                  Comment


                  • #24
                    No, I would buy a brand new virgin block and build a 377. a 383 is a 0.030" overbore in addition to the 3.75" stroke crank

                    read this (in its entirety) https://forums.iboats.com/forum/engi...-a-383-stroker

                    there are GMPP links, etc.

                    a new 377 is $4200, a reman stroker from someone not price-gouging would be about $3k talk to your local machine shop

                    I built my 468 for less than $3k
                    Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

                    1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

                    Past Boats
                    1970 Wooster Hellion - Merc 9.8
                    2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
                    1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                    What’s behind you doesn’t matter.Enzo Ferrari

                    Comment


                    • #25
                      Originally posted by Scott Danforth View Post
                      No, I would buy a brand new virgin block and build a 377. a 383 is a 0.030" overbore in addition to the 3.75" stroke crank

                      read this (in its entirety) https://forums.iboats.com/forum/engi...-a-383-stroker

                      there are GMPP links, etc.

                      a new 377 is $4200, a reman stroker from someone not price-gouging would be about $3k talk to your local machine shop

                      I built my 468 for less than $3k
                      sounds good so i was reading here and it says to repower the 87 it might need new parts. will i need a new intake manifold, electric fuel pump? also will my current power steering pump and other belt pulleys hook right up to this 6.2 from center state? also u stated in the other forum about the intake manifold and a 715cfm carb hooked up, u also mentioned new mainfolds for the exhaust. i believe i have a 600 holley and i have brand new exhaust manifolds and risers for my current 5.7. would i need a upgraded carb and get new exhaust manifolds aswell?
                      http://vi.vipr.ebaydesc.com/ws/eBayI...rsion=d04531b9
                      Last edited by cowlotter; October 9th, 2019, 01:52 PM.

                      Comment


                      • #26
                        yes, vortec heads have different bolt pattern for the intake
                        vortec blocks (unless you go GMPP block) do not have a mechanical fuel pump pad that is machined

                        your exhaust manifolds will bolt to any SBC (from 1954 to today)

                        600 CFM is a bit small for a stroker
                        Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

                        1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

                        Past Boats
                        1970 Wooster Hellion - Merc 9.8
                        2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
                        1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                        What’s behind you doesn’t matter.Enzo Ferrari

                        Comment


                        • #27
                          Originally posted by Scott Danforth View Post
                          yes, vortec heads have different bolt pattern for the intake
                          vortec blocks (unless you go GMPP block) do not have a mechanical fuel pump pad that is machined

                          your exhaust manifolds will bolt to any SBC (from 1954 to today)

                          600 CFM is a bit small for a stroker
                          so just a new intake manifold, fuel pump and carburetor if i did the conversion? the old belt pulleys will bolt right up with my old power steering to and is there any other new parts id need?

                          Comment


                          • #28
                            keep it a 5.7 and your 600 CFM would be fine
                            Cheesehead boating the Gulf Coast of FLA 27.51° N, 82.53° W

                            1988 Cruisers Rogue 2420 -VP 290 DP now powered by custom 468 - https://forums.iboats.com/forum/owner...988-rogue-2420

                            Past Boats
                            1970 Wooster Hellion - Merc 9.8
                            2002 SeaRay 190BR - 5.0 - A1G2 - "Cheeseheads in Paradise"
                            1984 Avanti 170DLI -3.0 stringer- "Ship Happens"

                            What’s behind you doesn’t matter.Enzo Ferrari

                            Comment


                            • #29
                              Originally posted by Scott Danforth View Post
                              keep it a 5.7 and your 600 CFM would be fine
                              the easiest way say is grab this , http://centerstateengine.com/new-mar...-1996-present/ , throw all my current parts on it and call it a day except a new intake manifold since its vortec? or would i have to do the 87 - 96 pre vortec block and no intake manifold?
                              Last edited by cowlotter; October 9th, 2019, 02:59 PM.

                              Comment


                              • #30
                                Sign up today
                                Originally posted by Scott Danforth View Post
                                without pulling it apart, its a guess

                                could be valve train, could be broken piston, could be bearings.

                                either way, your motor is coming out.
                                since ill probably be replacing the motor but i cant until next spring would i be fine not changing engine oil or filter during winterizing this season and just treat gas, fuel filter and drain water and call it a day. im trying to avoid spending money on something im going to replace anyways. what are your thoughts?

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