Need help figuring compression ratio
#1
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Need help figuring compression ratio
What i have is a 6.0 iron bored .040 using stock rods n crank n pistons are flat tops. Machinist said from his calculations the piston tops come above the deck .02 (this normal?) , heads are 243's plan on milling. 010 to clean them up n bump compression just a tad bit. Running a 224/230 .604/.609 lsa 112 and planned on using stock lq9 head gaskets. Whats my comp ratio gonna be? Any issues that stand out on this setup?
Thanks in advance
Thanks in advance
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Not sure on exact chamber size whatever stock 243's are milled.010. Just wondering if its even worth doing just. 010 or go more depending on ptv and compression #'s. I wanna be able to run 93lq4 octane w/o detonation issues.
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The following is a URL that you can use to correctly calculate your compression ratio:
http://www.kb-silvolite.com/calc.php?action=comp
Another thing to be aware of is that an aluminum LS block grows vertically 0.012-inches from 70 degrees F to 190 degrees F. If your piston is 0.002-inches above the block deck cold, it will be 0.010-inches below the deck when the engine warms up.
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http://www.kb-silvolite.com/calc.php?action=comp
Another thing to be aware of is that an aluminum LS block grows vertically 0.012-inches from 70 degrees F to 190 degrees F. If your piston is 0.002-inches above the block deck cold, it will be 0.010-inches below the deck when the engine warms up.
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#8
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That KB silvolite link is great. Find your cam timing specs and plug everything in. Dynamic compression is the important thing here. I believe that the max recommended for pump gas is 9.5 dynamic. That's what my engine is, never a knock at 29 degrees timing on 92 pump gas. Yes, a stock engine is .005 piston above the block, yours is fine.