INTERNAL ENGINE MODIFICATIONS Valvetrain |Heads | Strokers | Design | Assembly

243 Heads on a 4.8

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Old 06-13-2010, 01:37 PM
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Default 243 Heads on a 4.8

I found what I think is a pretty good deal on some stock 243 heads with Patriot .660 lift springs, titanium retainers, and 1.750 rockers. If I end up buying them I would probably send them in to be ported.
If I understand it right these heads will up my compression ratio. As of now I'm running pretty much stock but there are long tubes, a cam, and a wet kit in my near future.
Would there be any negatives to me going with these heads?
Old 06-13-2010, 02:06 PM
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in stock form these will lower your cr...you would need to have them milled to 61cc or less..not sure how efficient it would be with the smaller bore of the 4.8......
Old 06-13-2010, 11:52 PM
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4.8's coming outta the factory now are coming with 243/799 heads. If you're sending them off to get ported, I'd mill them a bit to at least the bowl size of a stock 862/706 head or maybe even a bit more to get some nice compression.
Old 06-14-2010, 02:47 AM
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Pretty sure you'll have to resurface 243s quite a bit to gain compression, might even have poor intake fitment after. Ask Richard from west coast cylinder heads what he would recommend.
Old 06-14-2010, 10:24 PM
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From my reading, folks are going .030" to get down to around 60cc. Stock is what 59cc? And no, you won't have intake alignment issues with .030" milled.
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