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Discussion Starter #1 (Edited)
Heads for se class motor

I HAVE A SET OF GM 441X HEADS 80 CC ,I AM 4th IN THE HOLD, DO I RUN A 40th GASKET OR A 24 th GASKET TO BE CLASS LEGAL IN S.E . THANKS
 

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I HAVE A SET OF GM 441X HEADS 80 CC ,I AM 4th IN THE HOLD, DO I RUN A 40th GASKET OR A 24 th GASKET TO BE CLASS LEGAL IN S.E . THANKS
Your question is confusing. A 441 or 441X head has a 76cc chamber, that would require .04 clearance between piston top and cylinder head (min). Is your piston .004 deep "in the hold"? If you are asking which gasket thickness to use, just do the math. Those heads need a (min) .04 deck height/gasket thickness, as per the rules. Hope that helps.
 

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Discussion Starter #3
phughes ss13. my heads cc at 80cc as per machine shop when I had them re worked he said that was what 1970 441x, with the larger intake runner had, I am 4th piston to deck in hole, the se rules do not show a 80cc head only a 76cc head with a 40th gaskt, with my 80cc heads can I get by with a 25th gasket and be legal. the SE rules show a 15th smaller gasket for every 4 cc increase.????
 

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phughes ss13. my heads cc at 80cc as per machine shop when I had them re worked he said that was what 1970 441x, with the larger intake runner had, I am 4th piston to deck in hole, the se rules do not show a 80cc head only a 76cc head with a 40th gaskt, with my 80cc heads can I get by with a 25th gasket and be legal. the SE rules show a 15th smaller gasket for every 4 cc increase.????
NO!! It is up to you to get the heads to 76CC or live with the larger chamber. If the heads were 66CC, you would still have to run the gasket for a 64CC head. The rules are based off GM nominal chamber sizes. The rules is for the MINIMUM chamber size for a given head gasket. You what to raise the compression, mill the head to 76CC.

BTW, I understand SS13 confusion. A 4th is a quarter of an inch, or .250, or two hundred fifty thousandths. Not .004



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I get it

phughes ss13. my heads cc at 80cc as per machine shop when I had them re worked he said that was what 1970 441x, with the larger intake runner had, I am 4th piston to deck in hole, the se rules do not show a 80cc head only a 76cc head with a 40th gaskt, with my 80cc heads can I get by with a 25th gasket and be legal. the SE rules show a 15th smaller gasket for every 4 cc increase.????
Now I understand your numbers, unfortunately the numbers in the rule book are non-negotiable. The specs in the rulebook are a minimum so your heads are legal at 80cc. With the piston .004 deep you need to find a .036 compressed thickness head gasket. Or just use a .04 gasket and be done with it. That would be your easiest path, should work well and not get you in any trouble with the rules Gestapo.

Are you planning on going to Lakeland??
 

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Discussion Starter #7
thanks I will either mill the heads or, find me a 36 thousang gasket,i will check and see whatever will give me the most compression.
 
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