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How to do a 383?

Discussion in 'The Garage' started by y5mgisi, Sep 12, 2004.

  1. y5mgisi

    y5mgisi 1 ton status

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    From what i understand its a 350 with a 400 crank. The block has to be clearenced for the biger crank though. Is this somthing i could do at home? I have acces to a vide veriety of machines at the school i go to and an extremly knolagable teacher So mabey i could do the machine work my self? Also i need to know what rods and pistons to use. Do i use the 350 or the 400 rods and pistons? /forums/images/graemlins/1zhelp.gif
     
  2. big83chevy4x4

    big83chevy4x4 3/4 ton status

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    well you can put the 400 pistons in a 350 block, you can use the 400 rods and the 350 pistons, or use the 350 rods and a special piston.

    AFAIK there really is no big clearanceing done to the block, mainly just rod bolts and such.

    the next motor ill build is a 383, prolly with a 6" rod /forums/images/graemlins/peace.gif /forums/images/graemlins/peace.gif
     
  3. 84_Chevy_K10

    84_Chevy_K10 Banned

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    400 pistons will not go into a 350 block without boring it .125 which we know is not acceptable.

    You can use 5.7" (350 rods) and custom stroker pistons
    5.565 (400) rods and stock 350 pistons
    Or 6" rods and special pistons made for them.

    I'd make my choice based on budget and choose 5.565" or 5.7" rods, probably with 5.7 getting the nod.

    Any machine shop you can find locally will likely be able to do the clearancing for you if they're punching the motor out and cleaning it up for you.
     
  4. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    When installing a 400 crank into a 350 block you must grind .200" off the mains so it will actually fit into the 350 block. You need to clearance the block so that the rod bolts don't hit the inside of the block and also the rod bolts need attention so they don't make love to the camshaft. You must balance the engine since there will be a mixmatch of parts and the 400 was externally balanced. The best method to build a 383 is to use 350 rods (5.7") with special pistons. If you use a 6" rod then the wrist pin is into the oil ring and the longevity of the engine is comprimsed.
     
  5. 84_Chevy_K10

    84_Chevy_K10 Banned

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    [ QUOTE ]
    When installing a 400 crank into a 350 block you must grind .200" off the mains so it will actually fit into the 350 block. You need to clearance the block so that the rod bolts don't hit the inside of the block and also the rod bolts need attention so they don't make love to the camshaft. You must balance the engine since there will be a mixmatch of parts and the 400 was externally balanced. The best method to build a 383 is to use 350 rods (5.7") with special pistons. If you use a 6" rod then the wrist pin is into the oil ring and the longevity of the engine is comprimsed.

    [/ QUOTE ]

    Agreed 100% with those statements.

    Although I'd hardly call the rod bolts smacking the camshaft, "love making." /forums/images/graemlins/rotfl.gif

    Here with the cost of machine work, an aftermarket stroker crank is cheaper than having the mains turned.
     
  6. Blue85

    Blue85 Troll Premium Member

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    Yeah, it seems that stroker cranks are getting affordable and 400's can't be getting easier to come by. And if you can find a good 400, why not just run it instead of building a 383?
     

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