ACL Race Series Main Bearings for BMW N63B44 S63B44 0.001 Undersize

ACL Race Series Main Bearings — 0.001" Undersize for BMW N63B44 / S63B44 Brand: ACL High-performance main bearings engineered for BMW N63B44 and S63B44 4395cc V8 DOHC 4-valve engines. These Race Series bearings deliver precision, durability and improved load capacity for demanding motorsport and high-boost applications. Fitment: BMW N63B44, S63B44 (4395cc V8) Size: 0.001" undersize — for crankshaft machining tolerance Series: ACL Race Series — optimized for competition and high-stress environments Construction: Multi-layer alloy with robust backing and high fatigue resistance Benefits: Enhanced oil film stability, superior wear resistance, reduced seizure risk under high loads Ideal for rebuilt or modified engines where crank journals are reground to undersize. ACL Race Series bearings are manufactured to tight tolerances and tested for consistent thickness and roundness, ensuring reliable crank support and long service life even in boosted or high-RPM operations. Note: Always confirm journal dimensions and follow OEM/engine-builder specifications when selecting undersize bearings.