Connecting rod connects the piston to the crankshaft, two ends of linkage with active and passive components in order to convey movement and the hinged edge of the bar. Connecting rod is a critical part of automotive engine. It connects piston to crankshaft, forming a simple mechanism that converts reciprocating motion into rotating motion, transferring the force on piston to crankshaft for outputting power. Most of connecting rod is made of quenched and tempered steel as it has to bear tensile stress and bending stress.