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Discussion Starter · #1 ·
I have my 351c opened up and preparing to send it out to the machine shop.

It is currently .030 over and I am going to have them hone it out to .040 and then install a 408 stroker kit with dish top pistons. I am going to continue using my 4v closed chamber heads and want to figure out what the compression ratio will be. How can I figure out my total ccs, and/or have I supplied enough information for it so I can get a feel for the total compression.

According the manu of the kit the COMP. RATIO would be as followes for varying size chambers: 63cc =10.89-1, 67cc = 10.44-1, 76cc =9.57-1 with a 4 inch stroke
 

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I come up with 12.12 to 1. That includes bore +stroke, deck clearance of .050, head gasket .035 and a 63 cc combustion chamber ( 3.5515 cubic inches). I didn't include valve reliefs or the side of the piston to the ring, but that wouldn't change it much. My brother ran 4v closed chambers on a 400 and had to run dished pistons for that reason.
 

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If you run that much deck clearance its gonna knock like a son of a bitch... You can't have ANY deck clearance in a closed chamber C and have any hopes of running pump gas.

Dodge- Run zero deck, a standard head gasket, and with the 62cc chamber and the dishes you should be mid 10s to 1, I forget the exact figure (plus when I do my calculating I use 58cc for my Aussies). Zero decking with flat tops ends up with way too much compression, but without getting the clearance to zero it would knock too (no quench).
 

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Discussion Starter · #5 ·
I was planning a zero deck with the dished pistons. Its good to hear someone agree with that /forums/images/icons/wink.gif
 
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