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Calculating compression ratio

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Old 03-13-2011, 12:09 AM
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Dr L-88
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Default Calculating compression ratio
What compression ratio will this combination yield?

454 block .030 over, stock stroke, std deck height

TRW L2349 piston

Cast iron GM head #336781 open chamber with 113 cc chamber

Fel Pro composition gasket .039 compressed thickness

Thanks,
Rex
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Old 03-13-2011, 03:44 AM
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northern77
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Try this.
http://www.angelfire.com/fl/procrastination/motor.html
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Old 03-13-2011, 06:47 AM
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HamadUP
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I used this calculator (http://www.csgnetwork.com/compcalc.html) and it gave me 10.85.
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Old 03-13-2011, 09:28 PM
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trw
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Are you sure on the 781's at 113?
If running a stock deck, use the steel shim head gaskets.
Hope this helps.
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Old 03-13-2011, 10:28 PM
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Dr L-88
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Originally Posted by trw
Are you sure on the 781's at 113?
If running a stock deck, use the steel shim head gaskets.
Hope this helps.

Both of these sites show 113 cc, I found another site that says 118 cc.

http://www.minuit10.net/EngineCode/c...linderHead.htm

http://www.nastyz28.com/bbcmenu.php
Last edited by Dr L-88; 03-13-2011 at 10:31 PM.
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Old 03-14-2011, 12:11 AM
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With your specs about 10.6, but I agree with trw, the 781s are probaly bigger.

At 118 you'd have around 10.2
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Old 03-14-2011, 01:43 PM
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CC the heads. Cheap and easy.
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