King Engine Bearings MB5520AM1.25 AM-Series Main Bearing Set Undersize - 1.25mm

The King Engine Bearings MB5520AM1.25 is an AM-Series Bi-Metal Aluminum Main Bearing Set engineered for Opel C20XE, X18XE, and X22XE engines. This set is sized at 1.25mm undersize, making it well-suited for engine rebuilds where the crankshaft journals have been reground to accommodate worn or damaged bearing surfaces.

King's AM-Series bearings are manufactured using a bi-metal aluminum construction equivalent to SAE-783 specification. This standard aluminum-based material provides reliable performance in low to medium load engine applications, offering excellent conformability and corrosion resistance for daily-driven and lightly modified engines.

Key Features:

• Bi-Metal Aluminum Construction — SAE-783 equivalent material for proven durability
• 1.25mm Undersize — Designed for reground crankshaft journals
• AM-Series — Ideal for OE-replacement and standard engine rebuilding applications
• Precision Manufacturing — Tight tolerances ensure proper oil film maintenance and crankshaft support
• Complete Main Bearing Set — Includes all required main bearing shells for the engine

King Engine Bearings has specialized in precision engine bearings since 1960, supplying high-quality bearing solutions for both OEM and aftermarket engine rebuilding worldwide. The MB5520AM1.25 is the correct choice when restoring proper bearing clearances on a reground crankshaft in the Opel XE/XE-family four-cylinder engines.