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Considering re-powering

Discussion in 'Technical Discussion' started by DetroitCoho, Aug 18, 2014.

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  1. DetroitCoho

    DetroitCoho Member

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    All good info, thanks for contributing
  2. Capt J

    Capt J Senior Member

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    You have to be careful of this. For example if you look at a SCAT (aftermarket/forged) crankshaft for a 454. I don't know what Dart may use for their crankshafts if you buy a short or long/block from them. The oil holes are radius'ed by scat for better flow and dispersion to the bearings BUT they are radius'ed in one direction for a standard rotation and a I think the radius would be counter productive if you reversed the rotation and even possibly create additional wear and a shortened life.
  3. SomeTexan

    SomeTexan Member

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    Dart is primarily heads and blocks. You can get them anywhere from a partially machined casting to ready to bolt together. Choose crank and internals to suit your needs. I've had good luck with Ohio crankshaft. They will build to spec, any changes you need for a minimal charge. It's been a while since I've ordered custom stuff from them, so that may have changed.
  4. Capt J

    Capt J Senior Member

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    Yes I know, I had a set of dart cast iron heads before. Dart does sell entire short blocks as well. It doesn't sound like the OP is going to build or assemble his own engine.
  5. SomeTexan

    SomeTexan Member

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    That is why I suggested a local performance shop. If a good builder has interest in doing a marine build, they could do a better job, cheaper than a marine crate engine. Plus, you would have the option of newer long rod set ups, newer head design, basically updated technology. It may not be the best option, but it shouldn't hurt to ask around a little.

    I did refer to the dart block after it was mentioned that the stock blocks are 5k each to replace.
  6. DetroitCoho

    DetroitCoho Member

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    OP here-thanks for all the info. I've pretty much decided that if I REPLACE the Ford 427s I'd do it with the 454 however, I still don't know if the torque will be where I need it for this boat (46' Chris Craft Roamer Riviera). The other engines (496, 502, etc) are exponentially more expensive and from what I've heard, will require doing things I don't want to do (tach conversion, gauge replacement, possible return fuel lines, new location for down angle, etc.)

    If the 454s are out because of inadequate torque, I think i'll have the original engines rebuilt. Of course, if I do that I understand I'm putting my investment back into vintage engines with a diminishing parts supply.

    Back to the 454s......would it be crazy expensive to get long blocks from First Mate, then using a Crusader parts manual, order all the rest of the stuff I need to make complete engines?
  7. Capt J

    Capt J Senior Member

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    I think if the 454's are propped correctly that they'll run just as good as the old 427's you have now. I think buying all of the Crusader parts piece meal would be very cost prohibitive. Honestly, If I was in your postion even being as knowledgable as I am, I would buy complete drop in engines. Are 502's that much more expensive?
  8. Old Phart

    Old Phart Senior Member

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    I dunno