N63 Pistons and Rings Set designed for use with N63B44 4.4L V8 Twin Turbo engines.This piston set fits specific models including 550i, 750i, X5, X6, and E-segment vehicles such as F01, F02, F03, E70, E71, as well as 5, 6, and 7 Series applications.The kit includes pistons and rings configured for standard bore specifications.Key specifications: Compression height: 32.1mm Length: 52.6mm Wrist pin length: 60mm Wrist pin diameter: Φ22mm Cylinder bore diameter: Φ89mm Engine compression ratio: 11:1 OEM part numbers included: 11257613626, 11257576475, 11257556955, 11257574822, 11257574823, 11257617547.Also compatible with equivalent part numbers from various suppliers.The set is intended for engine rebuilds and includes all necessary components for installation.Designed to meet fitment and function requirements.