Manley 290140R SBC 383ci Rotating Assembly 3.750" Stroke 4.040" Bore 1-Piece Rear Seal

The Manley 290140R is a complete 383 cubic inch Small Block Chevy (SBC) rotating assembly designed for builders looking to squeeze maximum displacement and torque out of the classic Chevy small block architecture. Featuring a 3.750-inch stroke and designed for a 4.040-inch bore, this kit converts a standard 350 SBC block into a high-performance 383 stroker — one of the most popular and proven engine combinations in American performance history.

Manley Performance is renowned for manufacturing precision-engineered, high-strength internal engine components used in everything from street performance builds to professional racing applications. This rotating assembly is built around Manley's commitment to tight tolerances and premium materials throughout.

Key Features:

• Engine Family: Small Block Chevrolet (SBC)
• Displacement: 383 cubic inches
• Stroke: 3.750 inches
• Bore: 4.040 inches
• Rear Main Seal: 1-piece (R suffix designation)
• Complete rotating assembly including forged crankshaft, connecting rods, and pistons
• Engineered for high-performance street and strip applications
• Designed for use with standard SBC 350 main bearing dimensions
• Compatible with 1-piece rear main seal blocks (mid-1986 and later style)

The 383 stroker combination is widely regarded as one of the best power-per-dollar upgrades available for the Small Block Chevy platform, delivering substantially improved low-end torque and overall horsepower compared to a stock 350. The Manley 290140R provides a solid foundation for any serious SBC performance build.