Even the finest, most accurate torque wrench on earth can only estimate the preload in a tightened bolt. If your engine build requires more accuracy than an estimate -- and they all do -- you need a stretch gauge. A stretch gauge is the only accurate way to measure bolt preload. A stretch gauge will also warn if any rod bolts have given up and are about to break.
This stretch gauge from ARP features a strong billet frame and heavy springs for consistent and repeatable measurements. Includes a protective carrying case.