N52B25 11:1 Pistons Rings Set Φ82mm 11257612982 11257561848 For E83 E90 E91 E60 E61 F10 F11 E89 323i 325i 523i 525i X1 X3 X4 Forged aluminum pistons and steel rings are used in the construction of this piston ring set.The design features an 11:1 compression ratio intended to support increased engine performance.It is engineered for use with specific vehicle models including E83, E90, E91, E60, E61, F10, F11, and E89 variants equipped with 323i, 325i, 523i, 525i, X1, X3, and X4 configurations. The set includes six pistons, six ring sets, and all necessary components for installation.The cylinder bore measures Φ82mm with a wrist pin diameter of Φ20mm, designed to match specifications for proper fitment within the engine block. This upgrade is suitable for naturally aspirated engines and aims to improve horsepower and torque output while maintaining durability under increased operational demands.The components are built to meet precise engineering standards for integration into engine rebuilds or performance modifications. Important: This is a non-OEM part.Any brand or model cited is used to denote device compatibility.