Eagle Chevrolet BB 4.000in Stroke Internal Balance Forged 4140 Steel Crankshaft

This is an Eagle forged 4140 steel crankshaft designed for Chevrolet Big Block engines. It features a 4.000-inch stroke and is set up for internal balance, making it a solid choice for builders looking to assemble a powerful, competition-ready engine. The non-twist forging process ensures that the crankshaft maintains its integrity under high stress, a critical factor when you're pushing an engine hard.

Eagle uses 4140 steel for its strength and durability, and this particular crank is further enhanced with a nitrided surface treatment and micropolishing. The nitride surface hardens the material, improving wear resistance, while the micropolishing creates an exceptionally smooth finish on the bearing journals. This smooth finish reduces friction and helps extend the life of both the crankshaft and your engine bearings. You'll notice the .125-inch fillet radii at the crank throws; these are designed for superior strength, but they do require chamfered or narrowed bearings to ensure proper clearance and oil flow.

This crankshaft is intended for competition use, meaning it's built to handle the demands of racing and high-performance applications. If you're building a race engine or a serious street/strip powerplant for your Chevy BB, this Eagle crankshaft offers a well-built foundation. Be sure to consult your engine builder or a trusted mechanic regarding bearing selection and installation to ensure optimal performance and longevity.