ACL BMW E30 M3 S14B20/23/25 I4 Connecting Rod Bearing Set (Oversize +.025)

This is a set of connecting rod bearings for your 1988-1991 BMW M3. These bearings sit between the connecting rod and the crankshaft, allowing the rod to spin smoothly while handling the forces from combustion. If you're rebuilding the engine in your E30 M3, especially with the S14 engine, replacing these bearings is a critical step to ensure proper oil clearance and long-term engine health.

This particular set is from ACL, a well-known name in engine bearings. They are manufactured to meet the specific demands of the S14 engine. The key detail here is that these bearings are +.025 oversize. This means they are intended for use when the crankshaft journals have been machined down by 0.025 inches to correct for wear or to achieve a specific clearance. Using the correct oversize bearing is essential for maintaining proper oil pressure and preventing premature wear after a crankshaft has been reconditioned.

When you're doing an engine rebuild, getting the bearing clearances right is crucial. These ACL bearings are well-built and designed to fit precisely into the connecting rods, assuming the crankshaft has been prepared for the +.025 size. Make sure you have the correct crankshaft specifications before ordering.