Main Bearing Set Nissan SR20DE/DET 91-98 4-Cyl

The ACL Bearings Main Bearing Set for Nissan SR20DE/DET 91-98 4-Cyl engines is a critical internal component engineered for builders and mechanics restoring or upgrading first-generation S-chassis platforms and other Nissan applications. This bearing set maintains precise crankshaft clearances under extreme rotational stress, making it essential for any engine rebuild, high-mileage service, or performance modification where factory tolerances have degraded. Whether you're refreshing a street engine or preparing a track-focused SR20 variant, proper bearing selection directly impacts reliability, longevity, and oil pressure stability.

ACL bearings are manufactured to strict OEM-equivalent standards with optimized aluminum backing and precise overlay thickness to ensure proper load distribution across the crankshaft journals. The standard thickness specification (1T2964-STD) matches factory tolerances and accommodates stock or slightly polished crankshafts without requiring crank rework. These main bearings feature advanced material compounds that improve film strength and reduce friction at idle and cruise, while maintaining load-carrying capacity during high-RPM acceleration or forced induction scenarios common in modified SR20 engines. The pair configuration ensures complete main bearing coverage for the four-cylinder layout.

Mechanics and engine builders working on SR20DE (naturally aspirated) or SR20DET (turbocharged) platforms will find this bearing set indispensable during full rebuilds, oil-gallery cleaning, or crankshaft replacement. Installation requires standard engine disassembly and block preparation, with clearance verification using Plastigage or dial bore gauges before final torque specs are applied. This bearing set is compatible with 1991–1998 Nissan SR-series four-cylinder applications and should be paired with corresponding rod bearings and thrust washers as part of a complete rotating assembly overhaul. Proper break-in procedure and quality synthetic oil are recommended to seat bearing surfaces and maximize service life.