ARP Rod Bolt Stretch Gauge

We highly recommend using a stretch gauge when installing rod bolts and other fasteners, where it is possible to measure the length of the fastener. It is the most accurate way of measuring preload of any bolt. When using a stretch gauge it's best to measure the fastener prior to starting and monitor overall length during installation. When the bolt has stretched a specified amount, the correct preload or clamping force has been applied.