King Engine Bearings MB5220SI0.25 Main Bearing Set Undersize Subaru - 0.25mm EJ20/EJ22/EJ25

The King Engine Bearings MB5220SI0.25 is a premium SI-Series main bearing set designed for Subaru EJ20, EJ22, and EJ25 engines, including turbocharged applications. This set features a 0.25mm undersize specification for engines with turned crankshafts.

Advanced SI-Series Material Technology:

• Bi-metal construction with aluminum blended with 2.5-3% silicon for enhanced strength
• Lead-free, environmentally safe composite material
• Optimized for medium-load engines with nodular cast iron crankshafts
• Improved crankshaft finish compatibility reduces microscopic ferrite peaks
• Enhanced oil clearance reduces wear and increases engine life

Complete Main Bearing Set:

• Set includes 5 pairs of main bearings
• Thrust bearing positioned in #3 location
• Precision tolerance control up to +/- .0001 inch
• OE-replacement quality for gasoline engine rebuilding
• Ideal for performance engines with factory crankshafts

King Engine Bearings specializes exclusively in engine bearing manufacturing, ensuring the highest quality materials and most advanced designs. The SI-Series represents the ideal balance of durability and performance for street and moderate performance applications, with reduced operating noise, vibration, and optimized oil flow characteristics.