Manley 38555X Big Block Chevy 555 CID Rotating Assembly Kit 4.250" Stroke / 4.560" Bore / -3cc

The Manley 38555X is a complete Big Block Chevy (BBC) 555 cubic inch rotating assembly kit designed for serious performance engine builders.

This kit includes Manley's signature "X" series rod bearings, which feature .001" extra clearance for high-performance and racing applications requiring looser tolerances. The rotating assembly is factory balanced to within +/- 1% of bobweight, saving critical machine shop time during the build process.

Key Features:

• 4340 forged steel crankshaft — heat treated, stress relieved, shot peened, nitrided, and 100% Magnafluxed for maximum strength and durability
• 4340 forged steel H-beam connecting rods with 7/16" ARP 8740 cap screws standard (rated to 900 hp); optional ARP 2000 cap screws available for up to 1,500 hp
• 2618 Platinum Series forged aluminum pistons with -3cc flat-top design for optimal compression tuning
• Premium chromoly wrist pins for high-RPM stability
• Total Seal piston rings for superior sealing and reduced blow-by
• Clevite "H" Series narrowed rod bearings and "P" or "H" Series main engine bearings included
• "X" series rod bearings with .001" extra clearance (denoted by the "X" suffix on the part number)
• Factory balanced to within +/- 1% of bobweight
• Designed for standard deck Big Block Chevy blocks

The Manley 38555X is engineered for performance enthusiasts and professional engine builders seeking a proven, complete bottom-end solution for Big Block Chevy stroker applications. All components are precision-matched to work seamlessly together, reducing guesswork and ensuring consistent, repeatable results on the dyno and at the track.