New main caps or old

Big Block A body Tech

  1. challenger57

    challenger57 cuda57

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    I'm in the process of building a 400-471 stroker with the expectation of about 600-650 hp. I was told the old main caps can handle this (street driven only) or should I get new forged caps and have it align bored. Has anyone here used the 440 source caps since that is where I am getting my stroker kit from. I am trying to consider this a one stop shop and get most of my build from them including their cnc ported heads and 1.6 roller rockers. Any pros and cons on this??? Thanks
     
  2. 1970Duster

    1970Duster Well-Known Member

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    I'd go New forged caps and a stud girdle, and call it done.
     
  3. 66V100

    66V100 Well-Known Member

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    I would go with aluminum main caps.
    The steel on steel in stroker apps puts a lot of stress on the main webs, and transfers it to lower cyls as well. The aluminum caps will "soften up the hit." alum caps flex, steel caps just snap. just my .02, am sure some that havnt seen broken steel caps or broken lower cylinders (esp on major thrust side) will dissagree. The new caps will need to be sized to the block.
     
  4. oldkimmer

    oldkimmer FABO Gold Member FABO Gold Member

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    ................I vote 4 alum caps also...............kim.........
     
  5. crackedback

    crackedback FABO Gold Member FABO Gold Member

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    At that level aftermarket caps aren't really needed. If you planning on stepping it up and going over 700hp on a B block, then start looking at main caps.

    Here's another thing to chew on. If you do go over the 700 mark, start thinking about an aftermarket block. I spent a good chunk of change on alum caps, machine work on a 400 block. It would have been a bit more to get a better piece to start with.
     
  6. JohnRR

    JohnRR This space for Rent

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    Buy something other than their rocker arms .
     
  7. moper

    moper FABO Gold Member FABO Gold Member

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    You dont need caps. Have the mains studded and align honed and run it.
     
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