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L92 heads

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Old Dec 30, 2008 | 02:28 PM
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Default L92 heads

Why wouldn't the L92 heads work in replacing our Ls6 heads? The GTO guys are replacing there Ls6 heads with the L92s, naturally they should just bolt in........no?
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Old Dec 30, 2008 | 02:55 PM
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i think the intake runners might be different and we are kinda stuck with what we got for intake manifold.
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Old Dec 30, 2008 | 07:46 PM
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Cylinder bore is too small on the ls4. And yea that intake.
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Old Dec 31, 2008 | 07:36 PM
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Originally Posted by neilownz
i think the intake runners might be different and we are kinda stuck with what we got for intake manifold.
Our cars use the same 243 heads that were available on the LS6 and LS2 engines sans the hollow valves and stronger springs.
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Old Jan 1, 2009 | 10:50 AM
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So the L92s will easly bolt on in place but not give you any hp over the Ls6 because of the intake runners??
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Old Jan 1, 2009 | 11:16 AM
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those heads are way to big for 325 cubic inches unless you want a pretty serious street/strip car, for which our cars does not have a stout platform for. you will need a minimum bore of 4 inches which the ls2 block has.
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Old Jan 1, 2009 | 11:16 AM
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Negative. The L92 heads require a minimum 4" cylinder bore diameter. Our LS4's only have 3.78". I'm not familiar enough with our motors yet to know if we could bore the LS4 to 4" or not.. but I doubt it! 0.22" is a lot of meat!
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Old Jan 1, 2009 | 02:26 PM
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it would require resleeving or not using sleeves
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