Maximum PSI teamed up with Manley Performance to create a heavy duty connecting rod set for the S55 and N55 BMW inline six cylinder engines. The factory components are quite capable, however we try to limit torque to around 600 ft/lbs on stock S55 engines. You can see the end result of pushing a factory connecting rod beyond those levels in the photo gallery. These rods are not compatible with OEM pistons. They are machined for aftermarket pistons with a non-tapered wrist pin/small end. We highly recommend combining with our forged pistons here.