Part Number: FCPPB840090M50 Manufacturer: FCP Engineering Forged high-performance pistons for a variety of applications in almost all types of engines for racing and street use. Made of 4032-T6, the bottom of the piston is molybdenum coated. Each piston set also includes HD series rings and pins. Cylinder diameter: 84.00 mm Compression Ratio (CR): 9.0:1Compression height: 32.50 mmPin diameter: 22mmStroke: 84.00 mmBMW 328 528 Turbo (M50B28, M52B28)Connecting rod length must be 135mmThese pistons are intended for the BMW 2.8 M50B25 engine with a changed M52B28 crankshaft!