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 Pistons and rings set designed for N52B25 2.5L L6 naturally aspirated engine with compression ratio 11:1.Cylinder bore diameter is Φ82.00mm.Wrist pin diameter is Φ20mm with a length of 46mm.Ring thickness: 1st ring 1.2mm, 2nd ring 1.5mm, 3rd ring 2.0mm.Standard specification with no cylinder expansion required.Set includes 6 pistons and rings.Compatible with vehicle models including E83, E90, E91, E92, E93, E60, E61, F10, F11, E84, E85, E89.Fits engines requiring OE numbers 11257612982, 11257561848, 11257561844, 11257542057, 40407600, 40444600, 31-04619-000, WG1016610.Applications by model: 323i – 2005–2011 (E90, E91, E92, E93) 325i / 325xi – 2006–2011 (E90, E91, E92, E93) 523i – 2005–2011 (E60, E61, F10, F11) 525i / 525xi – 2005–2010 (E60, E61) X1 – 2009–2012 (E84) X3 – 2006–2010 (E83) Z4 – 2006–2011 (E85, E89)