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Discussion Starter #1
I just recieved my new Dart SS heads. I am pulling off the smog heads on the 290hp crate and installing the Darts. The old heads have 76cc combustion chambers and the new ones have 67cc combustion chambers. I think with these new heads I should get around 9.1 to 1 compression ratio (up from 8 to 1 CR with the old big chamber heads) using a standard Fel-Pro 1003 (.041 thk) head gasket. Do you think if I used the Fel-Pro 1094 shim gasket (.015 thk) that would be too much? I am guessing that would get me up to around 9.3 to 1 compression ratio with these heads.

Thanks in advance---
 

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the shim gasket should yeild you another .5-.7 on compression some where in there. so if you were to be at 9.0-1 with the .41 gasket than count on at least 9.5-1 with the shim gasket.
 

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what they were saying ^^^^^

if they block has been decked i would find out how much exactly. you can go .036 from piston to head clearance on a small chevy . but i would suggest the .040 for a street car. if the block hasnt been decked do the .015, that will give you your.040. getting the tightest quinch area is key to making an afficiant combo.
 

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Discussion Starter #6
Just got the old heads off the car but still have to clean everything up and get ready for the new head install.

Appreciate the advice guys.
 
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