Calculating compression ratio
Mar 13, 2011 | 12:09 AM
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Le Mans Master
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From: Richmond Kentucky
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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
Mar 13, 2011 | 03:44 AM
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From: Pulaski Wisconsin
Mar 13, 2011 | 06:47 AM
Mar 13, 2011 | 09:28 PM
Melting Slicks
Joined: May 2000
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From: Crescent City, CA
Are you sure on the 781's at 113?
If running a stock deck, use the steel shim head gaskets.
Hope this helps.
Mar 13, 2011 | 10:28 PM
Thread Starter
Le Mans Master
Joined: Oct 2007
Posts: 6,001
Likes: 1,742
From: Richmond Kentucky
2025 Corvette of the Year Winner- Modified
2024 C2 of the Year Winner - Modified
2022 Corvette of the Year Finalist -- Modified
2021 C2 of the Year Winner - Modified
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2020 Corvette of the Year (stock)
C2 of Year Winner (stock) 2019
2017 C1 of the Year Finalist
Quote:
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; Mar 13, 2011 at 10:31 PM .
Mar 14, 2011 | 12:11 AM
Le Mans Master
Joined: Oct 2000
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From: Austin TX
With your specs about 10.6, but I agree with trw, the 781s are probaly bigger.
At 118 you'd have around 10.2
Mar 14, 2011 | 01:43 PM
Race Director
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From: Millington Illinois
St. Jude Donor '08-'09
CC the heads. Cheap and easy.
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