E90 / E91 / E92 / E93 335is N54

or S52 valvetrain with a Ferrea Valve Kit for superior heat resistance

SPRK-2521-2BM-T1

G30 540i B58

Boost pressure: 8-9 PSI

5150 Xtreme Duty Cylinder Sleeve Set, BMW S63 S65B46 E90 / E91 / E925150 Xtreme Duty Cylinder Sleeves, also known as cylinder liners, are centrifugally cast, ductile iron cylinder sleeves. Benefits of Engine Sleeving Include: Increased Bore Size: Sleeving your engine gives the opportunity to increase bore size for higher displacement and increased engine capacity, resulting in more power and more torque Increased Strength: Iron sleeves are stronger than alusil when subjected to high power, high stress applications,