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5.3L c/r not adding up

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Old 03-02-2017, 11:17 AM   #1
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Default 5.3L c/r not adding up

Im new to LS engines amd am planning a build very soon. But nothing is adding up. Where am i getting my math wrong on engine compression.
5.3L LM7 with 862 stock heads
Bore: 3.78
Stroke: 3.62
Cylinders: 8
Pistion cc: 2cc
Head cc: 61cc
Head gasket: .040
Pistion Height: .007

Everything is telling me crazy **** like 10.7:1 when known ratio is 9.5:1
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Old 03-02-2017, 12:05 PM   #2
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After doing some tinkering on here and plugging away at numbers i suppose my pistons are the 9cc dishes rather than the 2cc flat tops.
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Old 03-02-2017, 01:32 PM   #3
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Stock engine?

You would have dished pistons, and a .051" headgasket most likely.
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Old 03-02-2017, 02:05 PM   #4
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Originally Posted by JoeNova View Post
Stock engine?

You would have dished pistons, and a .051" headgasket most likely.
Yes, 100% stock, im mapping out a JY build like many.
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Old 03-02-2017, 08:52 PM   #5
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flat top 4.8/5.3 stamped blocks are 4.8's so you should have the dished.
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