Stretched Head bolts can lead to blown head gaskets and overheated engines. Head Studs offer a alternative when its time to reseal a engine head. Bolts when torqued are affected by two difference forces. The bolt stretches and twists. A Headstud will not twist as only the nut is torqued down. This allows them to add more clamping force and helps reduce the chance of burning up a gasket.
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