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Casting #781 heads on a 496?

Discussion in 'The Garage' started by eldon519, Jul 15, 2003.

  1. eldon519

    eldon519 1/2 ton status

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    Location:
    Kennesaw, Georgia
    I could use some advice. I'm trying to build a 496 or maybe a 489 stroker(so i could use the block again) and I recently found some 781 cylinder heads which I have heard are one of the best flowing large oval port heads. Do you think they will be big enough to support this big of an engine? I'm not really concerned with horsepower. I want to achieve around 550 lb-ft if I can so I figure HP will fall maybe in the 400 to 450 range with a fairly low RPM band. Also, what work should I have done on the heads? They have 119CC open combustion chambers I believe so would it be helpful to have the heads milled and the deck height reduced so I can get a decent CR? I know i'm asking alot of questions but here is one final one, if I build the above engine, is it gonna eat my TH400? I am trying to tailor the truck for trail and crawling duty. Thanks in advance.
     
  2. Toledo

    Toledo 1/2 ton status

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    those heads should support that from what I have heard. as far as the technical what should you do to em I would ask the question under the performance section of www.chevytalk.com
     
  3. madmike

    madmike 1/2 ton status

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    I just finished assembling a 489 stoker, using a stroker kit from www.speedomotive.com, and their website claims that 119cc heads like yours, along with their stroker kit which has a slightly domed piston, will yield 9.5:1 compression. I don't think you would want to go much more than that on a street engine. I have a pair of #049 heads which supposedly have 119cc too, but I wasn't able to use them due to condition. I think the heads you have will work very well for what you intend to use the rig for, and they will make plenty of torque!

    I don't know anything about how the T400 may hold up, I use a SM465. Good luck!
     

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