Perfect Circle MS829H1 H-Series Main Bearing Set 0.001" Undersize Big Block Chevy

The Perfect Circle MS829H1 is a high-performance main bearing set designed specifically for Chevrolet big block V8 engines. This H-Series bearing set features a 0.001 inch undersize on the crankshaft journal, allowing for precise clearance control when tightening up bearing tolerances on slightly worn crankshafts or for achieving optimal clearances in performance builds.

Key Features:

• H-Series tri-metal construction with steel backing for superior strength and durability
• 0.001" undersize crankshaft journal dimension for tighter clearance control
• 1/2 groove design on upper bearing shell for efficient oil distribution
• Medium eccentricity and high crush factor for optimal performance
• Enlarged chamfers for improved crankshaft fillet clearance
• Suitable for medium-to-high RPM applications

This bearing set is compatible with Chevrolet big block engines including the Mark IV, Gen V, Gen VI, and Gen VII families. Fits engines such as the 366, 396, 402, 427, 454, and 502 cubic inch V8 engines found in 1965-2000 Chevrolet and GMC trucks and passenger vehicles. The H-Series bearings were originally developed for NASCAR racing applications but are well-suited for any performance engine build requiring precision clearance control.

The H-Series design features no flash plating for improved bearing seating and is ideal for engines that operate at medium-to-high engine speeds. The 0.001" undersize allows machinists and engine builders to achieve precise oil clearances, typically used when fine-tuning bearing clearances or compensating for minor crankshaft wear.