ACL Race Series Main Bearings 5M1219H-.25

ACL Race Series Main Bearings – 5M1219H-.25 ACL Race Series main bearings 5M1219H-.25 are precision-engineered for high-performance Mitsubishi 4G63 and 4G64 engines, including 7-bolt EVO models V–IX. These 0.25mm oversized main bearings deliver superior durability and tight clearances needed for race and high-boost street applications. Key Features Fitment: Mitsubishi 4G63 / 4G64, 7-bolt EVO V–IX Size: 0.25mm oversized to accommodate crankshaft regrinds Construction: Multi-layered, high-fatigue alloy backing with precision PTFE-infused overlay for enhanced wear resistance Performance: Designed for high RPM, boosted, and race engines—offers improved oil film stability and reduced risk of edge loading Durability: Enhanced load capacity and thermal stability for extended service life under extreme conditions Why Choose ACL Race Series ACL Race Series bearings are the choice of engine builders who demand consistent clearances, superior metallurgy, and tight manufacturing tolerances. The 5M1219H-.25 set ensures reliable crank support after machining, minimizes bearing wear, and helps protect your short block during high-stress operation. Application Tip: Always verify crank journal sizes and follow OEM or machine shop tolerance recommendations during installation.