LM4 5,3L with 799/243

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Apr 13, 2012 | 09:06 PM

btlegacy

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From: NC

LM4 5,3L with 799/243

I am looking at putting 799/243 heads on an LM4 5.3L Motor that came out of a Rainier. What kinds of compression will that give me an how much should I mill the heads and what gasket to run?

Apr 13, 2012 | 09:40 PM

2000chevysilverado

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From what I've learned need to mill them .030 to get stock compression

Apr 13, 2012 | 09:44 PM

TXSZ66AVLANCHE

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If it came from a ranier it should already have those heads

Apr 14, 2012 | 12:55 AM

btlegacy

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The motor has 706 heads currently. You may be thinking of an L33

Oct 24, 2012 | 06:02 PM

btlegacy

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We ended up milling the heads 0.030 which should put us at 9.9:1

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