8pcs 11257613626 11257574823 11257556955 11257617547 Pistons & Rings Set For 550i 750i X5 F01 F02 F03 E70 E71 N63 4.4L V8 Material: Forged Aluminum Compression Height: 32.1mm Length: 52.6mm Pin/Bolt Length: 60mm Pin/Bolt Diameter: Φ22mm Cylinder Bore Diameter: Φ89mm Fitment: Designed for N63B44 4.4L (4395cc) V8 Twin Turbo Engine function: Compression ratio of 11:1 Package Contents: Pistons & Rings Set x 1 This pistons and rings set is engineered for vehicles equipped with the N63 4.4L V8 engine, including models 550i, 750i, X5, F01, F02, F03, E70, and E71.The forged aluminum construction supports improved combustion efficiency and increased power output.Each piston is designed with a compression height of 32.1mm and an overall length of 52.6mm to align with engine specifications.The pin/bolt diameter measures Φ22mm with a length of 60mm, secure integration within the engine block.The cylinder bore diameter is Φ89mm, allowing precise fitment.This set includes eight pistons with matching rings, optimized for function applications.