Gen I Head Tourque specification???

RT/ED

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The service manual states that head bolts on a Gen I should be tourqued to 30 pounds then 1/4 turn. Can this be true? 30 pounds seems very low for head bolts. Can anyone either confirm or correct this specification? :usa:
 

Viper Wizard

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Yes that is what the book says, you end up at 95 ft lbs. Are your replacing your head gaskets with the new multi-layered steel gaskets? If so "Torque Sequence" as follows: 40 then 80 and final torque is 120 ft lbs!
1/4 turn is for the old gaskets!
 

Jack B

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With the earlier/thinner head gasket, once the gasket is fully compressed (@30 ft lbs) you then begin to compress the head and it is basically incompressible. At that point most of the torque is merely stretching the bolt. When you reach the final torque the bolt becomes a spring holding down the head.

The key to the whole process is taking the bolt to the right torque value. Typically you take a bolt to a value that is less than results in permanent elongation. It seems as these bolts are worked closer to the permenant elongation value, thus, the reason the Gen 1 bolts cannot be reused.

A similar analogy is a spark plug with a gasket. It might take over one turn (after hand seating)to compress the gasket, at that point it will take less then a quarter turn to reach the proper torque value.
 
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