King Engine Bearings MB639XP025 XP Series Main Bearing Set 0.025" Undersize

The King Engine Bearings MB639XP025 is an XP Series performance main bearing set machined to a 0.025" (0.25mm) undersize specification, designed for engines requiring precision crankshaft main bearing replacement during rebuild or performance builds.

King's XP (Extra Performance) Series bearings feature a tri-metal construction engineered to exceed OEM specifications, delivering superior load capacity, improved oil film retention, and enhanced wear resistance compared to standard replacement bearings. The XP Series is a popular choice among professional engine builders and performance enthusiasts who demand consistent tolerances and long service life.

Key Features:

• XP Series tri-metal construction for superior strength and durability
• 0.025" undersize for use with reground or worn crankshafts
• Precision-machined to tight tolerances for consistent oil clearance
• Enhanced overlay for improved embedability and conformability
• High fatigue strength to withstand elevated loads in performance applications
• Manufactured to meet or exceed OEM specifications

King Engine Bearings are made in Israel and are trusted by professional engine builders worldwide. The MB639XP025 is the correct choice when crankshaft journals have been reground to the 0.025" undersize specification.