King Engine Bearings MB 427AM1.0 AM-Series Main Bearing Set Chevrolet 173 V6 +1.0mm

The King Engine Bearings MB 427AM1.0 is a complete crankshaft main bearing set designed for the Chevrolet 173 V6 engine. This set is part of King's industry-proven AM-Series line, offering a reliable OE-replacement solution engineered for standard passenger car rebuild applications.

Built using King's standard bi-metal aluminum (Alecular) construction, the AM-Series bearing material is the softest and most conformable in King's lineup, making it ideally suited for engines with low to medium load demands. The bearing set is supplied at a +1.0mm crankshaft undersize, accommodating reground crankshafts machined to that specification. The set includes 4 pairs to fully service all main journal positions.

Key Features:

• AM-Series bi-metal aluminum construction — King's standard Alecular material (SAE-783 equivalent) optimized for low to medium load engines
• 100% lead-free — environmentally friendly and user-safe formulation
• Superior embeddability — thick Alecular layer absorbs macro-particles to reduce crank journal scratching and bearing damage
• Tight tolerance control — manufactured to within ±0.0001" for precise oil clearance and long engine life
• High temperature threshold — Alecular bi-metal withstands up to 662°F (350°C), significantly exceeding traditional tri-metal designs
• +1.0mm crankshaft undersize — fits crankshafts that have been ground 1.0mm undersize
• Sold as a complete set — includes 4 pairs to service all main bearing positions

King Engine Bearings has been manufacturing precision engine bearings since 1960. Every bearing passes rigorous quality control checkpoints throughout the production process, ensuring consistent wall tolerance and reliable performance in every set.