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317s vs 243s

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Old 02-16-2009, 07:50 PM
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If you get ls6 243's the better valves are a plus too.
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Old 02-16-2009, 08:07 PM
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Originally Posted by Low_LQ4
Can't you just mill the heads to raise the comp up instead of buying new heads since they flow the same?
you would have to mill them .045-.050 to be the same as the 243 head
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Old 02-16-2009, 09:05 PM
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Originally Posted by dirt track racer 81
you would have to mill them .045-.050 to be the same as the 243 head
Then you could poss start running into intake fittment issues
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Old 02-18-2009, 09:02 PM
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Depending on your gaskets and such.....you could be looking at a 10.9 to 11.0 according to my handy dandy DCR calc.
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Old 02-19-2009, 12:16 AM
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off the original posters question

anyone know what the CR of a 5.3 with PRC stage 2.5 LS6 heads will be?
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Old 02-19-2009, 06:30 PM
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Flat tops or dished pistons?
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Old 02-22-2009, 11:02 PM
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I would guess dish? its stock rotating assy, 03 model.
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Old 02-23-2009, 04:59 AM
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It will probably be somewhere around 9:1
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