Victor Reinz Victor Reinz 14-55009-01 14-55009-01

Engine Cylinder Head Bolt Set. (14-55009-01) by Victor Reinz

Using new head bolts when performing a cylinder head installation is always a good idea however, on late-model engines that came from the factory with TTY (torque-to yield) head bolts, replacement is an absolute necessity. TTY bolts are designed to exert the maximum clamping force for a tight head gasket seal, however they permanently stretched and could fail if re-used.

When a specific tightening torque has been reached, the bolts are turned further through a defined angle, which pre-loads them into the plastic region. Consequently, no retorquing is necessary.