• The crankshaft is the main part of an engine's rotating assembly.Kurbelwelle image by martin filzwieser from Fotolia.com
  
  First produced in 1970, the Chevy 454 was based on the GM Mark IV block that was the basis for several different engine offerings from Chevrolet. By maximizing the Mark IV block's cylinder bores and adding a new crankshaft with a longer stroke, GM created an engine that displaced a total of 454 cubic inches. The crankshaft in the 454 remained relatively unchanged until 2000, when Chevy introduced improvements intended to increase durability and sealing.
  
  

Stroke/Journal Diameter

• All Chevy 454 crankshafts throughout their production had a 4.00 inch stroke. All 454 crankshafts have 2.75-inch-diameter main bearings and 2.20-inch-diameter rod bearings.
  
  

Oil Seals

• 1970 to 2000 454 cranks are designed for use with a two-piece rear main seal. 2000 and later 454 cranks are designed for use with a one-piece rear main seal that requires the use of a different main cap and are not interchangeable with those of earlier engines. 2000 and later special race-only versions of the 454 engine are designed with a crankshaft that uses a two-piece rear main seal.
  
  

Materials

• 2000 and later 454 stock production crankshafts are cast nodular iron. 1970 to 2000 454 cranks were either cast iron or forged iron depending upon the intended applications. 1970 to 2000 454 crankshafts intended for use in base model engines were typically of the cast iron variety, while forged units were used in performance applications for increased durability.
  
  

Balancing

• All 454 cranks are externally balanced using counter-weighted flywheels and flex-plates and require that the harmonic balancer be included in the balancing process.