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4age small port vs Big

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SplintWhisky
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2013/03/26 13:54:44 (permalink)
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4age small port vs Big

Hey guys
 
I was just wondering what the difference is between the small port and a Big port is. I want to buy a head for my engine and recondition it whilst adding some better cams and all that stuff. I cant buy a whole engine because I have no place to work on it because I am renting and me working on an engine outside of a car will, quote "scare the other tennents". So is there any difference at all between the two heads or is it only the block that is different
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    Knightrous
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    Re: 4age small port vs Big 2013/03/26 14:30:56 (permalink)
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    Bigport has big intake ports, which lack flow velocity down low and has TVIS on it to improve this along with an 8 runner intake manifold, they have 240 deg cams and the block has 9.4:1 compression.
     
    Smallport has smaller intake ports, they have a better flow characteristic and use 4 runner intake manifold, they have 232 deg cams and the block has 10.3:1 compression along with oil squirters.
     
    There are probably other things I have missed, but that's the jist of them.

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    SplintWhisky
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    Re: 4age small port vs Big 2013/03/26 15:00:59 (permalink)
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    So which would be better to recondition to place back on to my big block
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    just_ace
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    Re: 4age small port vs Big 2013/03/26 15:34:30 (permalink)
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    replace a big port with a big port so everything bolts back in.

    Unless you get all the intake manifold etc bits for the small port and your current ecu and wiring wil be happy with it.
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    SplintWhisky
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    Re: 4age small port vs Big 2013/03/26 16:41:56 (permalink)
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    OK so all the TVIS stuff wont just bolt on?
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    Knightrous
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    Re: 4age small port vs Big 2013/03/26 16:46:34 (permalink)
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    The TVIS intake will not work with a small port head.
     
    For your circumstances, it will be easier to just source another big port head.

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    Domma_aw11
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    Re: 4age small port vs Big 2013/03/26 18:29:00 (permalink)
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    or do what i did put a bigport head on a smallport block and everything goes back in :)
     
    but what the others have said makes very good sense..
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    blacky83
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    Re: 4age small port vs Big 2013/03/26 22:00:21 (permalink)
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    Yeah, the intake manifolds will only work with that particular head so its a bit of extra stuffing around. In stock form the smallport is better, but not considerably so to justify the expense of switching. Better off going for a 20V.
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    SplintWhisky
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    Re: 4age small port vs Big 2013/03/27 13:58:00 (permalink)
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    yeah i just want to work on the head and add better cams and a better headgasket
     
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    MCT_MR2
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    Re: 4age small port vs Big 2013/03/27 19:31:34 (permalink)
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    Or if you decide to run a smallport head, you can buy a big>small port adapter from techno tou tuning that replaces the TVIS plate.

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