Engine Swap Chrysler 318 to ????

Discussion in 'Inboards' started by sportfishermans, Oct 31, 2007.

  1. sportfishermans
    Joined: Oct 2007
    Posts: 3
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    Location: Muskegon, Mi

    sportfishermans New Member

    Well after a summer full of engine problems I pulled and tore down my 1973 Chrysler LM318 engine and found what I expected, its time for a rebuild. That said I have been giving some heavy consideration to swapping to a different engine. I found parts sourcing to be time consuming to say the least, and usually involved ordering over the web and waiting days for it to come, and even when it ran good the chrysler just never performed the way I had hoped.

    That said I have been considering trying to locate a mercruiser inboard driveline that I could swap in. My velvet drive is in great condition and i am not too worried about putting that behind my next engine if I can get ahold of a bellhousing to convert to the new bolt pattern.

    This is going into a 25' 1973 Trojan, and I was thinking I would go with a 351 or a 350 if I could find one in hopes that I might be able to cruise without having to floor the throttles, and in that parts are readily available. That said does anyone have an opinion on what I am thinking about doing? To me the biggest problem I see is rewiring, the mechanical work should be fairly straight forward in my opinion, but having limited experience with inboards I dont know if I am oversimpilifying this in my mind (I have years of experience working with I/O's and outboards)

    Any advice?
     
  2. Jango
    Joined: Aug 2005
    Posts: 519
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    Location: Mid Atlantic

    Jango Senior Enthusiast

    Sportfishermans, Shouldn't be a big deal at all swapping to a 350/351. Usually can find Bell Housings on Ebay. Engine mounts of course will be different. Wiring should only be different with connectors unless you're going to Fuel injection etc. Don't go to a Big Blk unless you have a 72C (1018)Velvet Drive.
    The 350 GM will probably be less expensive since they are more plentiful.
    I personelly prefer the Ford SM Blks. Not sure why other than they are slightly lighter and am more familiar with them. I have a 475HP Stroked 5.0 in my 20' custom runabout.

    Regards, Jango
     
  3. sportfishermans
    Joined: Oct 2007
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    Location: Muskegon, Mi

    sportfishermans New Member

    I have always been happy with my 351's as well. No worries about a big block, not looking for the power increase so much as easier to locate parts and a bit newer tech on the motor. Prefer carb for this one over fuel injection, dont want to over complicate it.
     
  4. mongo75
    Joined: Aug 2007
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    Location: Orange County California

    mongo75 Senior Member

    Hell, I'm dropping a 440 in place of I'm not sure, but it was either a 318 or a 360 in a 25' 1968 Luhrs Flybridge. She's gonna fly! LOL
     
  5. sportfishermans
    Joined: Oct 2007
    Posts: 3
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    Location: Muskegon, Mi

    sportfishermans New Member

    Just not enough room for a 440 :) I dont mind though, dont need the power really. Just want some reliability. That said the hunt continues. Any good advice on sourcing a bell housing? Been watching ebay but either my searches are crap, or they havent been on there.
     
  6. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    All 318 are NOT the same.

    There is an auto 318 , that is relativly small.

    There is the 318C which is still in use on compressors and other construction equippment . It if very close to the 440 with smaller cylinder sleves.

    These 318C are VERY robust and might already be in the boat?

    FF
     

  7. mongo75
    Joined: Aug 2007
    Posts: 262
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    Location: Orange County California

    mongo75 Senior Member

    Sorry you haven't had luck yet. I've seen a few on ebay in the past month of two- you just gotta look every day, like I do for a good fuel tank LOL. Are you wanting a 351? Although I'm a Ford guy at heart, you'll find more Chevy stuff on ebay any day of the week.
     
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