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Crankshaft - Forged Steel

Brand: Chevrolet Performance

Part Number: 12489436




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Small Block Crankshafts

A crankshaft is that massive piece of convoluted steel that holds the whole engine together. An engine is essentially a pump, and without a strong crankshaft, the pump won’t work. GM puts the same top-quality engineering and manufacturing processes into its crankshafts as it does all its parts. These crankshafts are the same ones used in Chevrolet Performance crate engines. The crankshafts are available in cast iron and forged steel. Forged crankshafts should be used for higher-horsepower applications.

Forged Steel Crankshaft

12489436 Chevrolet Crankshaft

  • Forged 4340 steel crankshaft used to create 383-cubic-inch engines with 3.800" stroke
  • Rod journals are 2.100"
  • Mains are standard 350 size

Notes:  Should be used with connecting rods P/N 19169670, bearing kit P/N 17800761, standard pistons P/N 88962748 or 0.030” oversize pistons P/N 88962749, balancer P/N 12498008, and 1986-and-later one-piece crank seal design flywheel or flexplate.