SBC 4340 Forged Crank 3.480 Stroke 350 Main

The EAGLE SBC 4340 Forged Crank 3.480 Stroke 350 Main is a premium forged steel crankshaft engineered for small-block Chevy engines demanding serious reliability and internal balance. This crankshaft represents the foundation of a high-performance engine build, where rotating assembly balance directly impacts power delivery, engine longevity, and drivability across all RPM ranges. The 3.480-inch stroke geometry is the industry standard for small-block displacement optimization, and EAGLE's forged 4340 steel construction provides the material strength and fatigue resistance required for boosted, high-revving, or competition applications.

This unit features internal balance, meaning counterweight masses are machined directly into the crank itself rather than relying on external balance weights. Internal balance delivers more precise rotational stability and eliminates the risk of balance-weight separation under extreme loads. The 350 main journal size is the correct specification for small-block Chevy applications, accommodating standard main bearings and ensuring proper oil passage flow to supporting journals. The two-piece seal design allows for straight crankshaft installation without flywheel removal, simplifying engine assembly and maintenance procedures. At 58 pounds, this forged unit is heavier than cast alternatives, a direct result of the superior material density and engineering precision required for durability.

Engine builders, hot-rodders, and restoration specialists select EAGLE forged cranks for street performance, bracket racing, marine, and off-road applications where rotating assembly integrity cannot be compromised. The 4340 material is the gold standard for cranks in turbocharged, supercharged, or nitrous-assisted builds, where peak cylinder pressures and inertial forces demand material properties beyond what cast iron can reliably deliver. This crankshaft integrates seamlessly into small-block Chevy engine families—including 283, 302, 327, and 350 variants—making it the foundation component for engine rebuilds and high-output street machines.