Part Number: FCPPA820085RS4Manufacturer: FCP EngineeringExtruded high performance pistons for a variety of applications in almost all types of engines for racing and street applications.Made from 4032-T6 material, molybdenum coated piston bottom.Each piston set also includes HD series rings and rods.Cylinder diameter: 82.00 mm Compression Ratio (CR): 8.5:1 Compression height: 30.80 mm Piston rod diameter: 21 mm Stroke: 86.40 mm Audi S4 RS4 - 2.7 30V Biturbo