BBC L/W 4340 Forged Crank - 4.000 Stroke

The BBC L/W 4340 forged crank with 4.000 stroke is the foundation of high-performance big-block Chevrolet engine builds, designed for serious enthusiasts and professional builders pursuing maximum displacement and power output. This crankshaft transforms stock engine architecture into a stroker platform, enabling larger total cubic inches without the expense of a full block replacement. Whether you're building a dedicated track engine, street rod powerhouse, or competition platform, this forged crank provides the structural integrity and precision needed for sustained high-RPM operation.

Manufactured from 4340 alloy steel and forged rather than cast, this crankshaft delivers superior strength-to-weight characteristics critical for engine reliability under boost, nitrous, or high-compression scenarios. The 4.000-inch stroke directly increases piston travel and combustion chamber dwell time, producing significant gains in low-end torque and mid-range responsiveness compared to factory specifications. Precision counterweight design minimizes vibration while the lightweight construction reduces rotational inertia, allowing faster acceleration and improved throttle response. At 74 pounds, this crank is engineered for both naturally aspirated and forced-induction applications where durability cannot be compromised.

This stroker crank suits builders planning 427+ cubic inch big-block combinations, fitting standard BBC block architecture with compatible pistons, rods, and timing components. Installation requires precise balancing to your specific rotating assembly weight and damper selection—critical for preventing harmonics that damage bearings and seals. Professional machine shops experienced in stroker builds should handle installation and balancing to ensure optimal clearances and longevity. Compatible with traditional BBC applications from 1965 forward, this forged crank enables the displacement and torque gains serious enthusiasts demand without frame-off redesigns.