That's known as a "torque-to-yield" bolt, and it can be used only once. The bolt actually stretches a given amount to apply the proper clamping force to the head. The head gasket problems were most common with dissimilar metals- - - -cast iron block/aluminum head, etc. The early Cadillac Northstar had massive head gasket problems until they cast the aluminum block material over the iron cylinder liners. The early ones had the iron liner exposed to the head, and it was almost impossible to keep the head gasket sealed.
Jerry
