• Chevrolet began producing its big-block engine series in the 1950s and 1960s. The most common big-block that Chevrolet manufactured was the 454. This engine was used in cars until 1974, after which it was placed exclusively in Chevrolet's trucks, like the Suburban and the C10. The 454 was used in various forms at least until 1996. To ensure engine stability, engine bolts must be torqued or bolted down to certain specifications set by the manufacturer.
  
  

Valve Cover

• In an internal combustion engine, there are a series of cylinders that house a moving ring-and-piston assembly. Within the cylinder block are valves, including poppet valves, which open and close the intake and exhaust ports within the cylinder head. Valve covers are responsible for covering these valves to prevent damage to the engine.
  
  

Torque

• Torque refers to the force required to rotate an object, in this case a nut or a bolt, around an axis or pivot. You can think of it as a twist. An engine manufacturer sets specifications for its components, such as torque specifications, which are expressed in foot-pounds. To ensure engine stability, engine bolts must be torqued or bolted down to a certain weight specification under manufacturer guidelines.
  
  

Specifications

• In this big-block engine, the valve cover requires 4.17 foot-pounds of torque to join properly with the cylinder head. The cylinder head attaches to the engine block with 80 foot-pounds of torque.
  
  The exhaust manifold requires 20 foot-pounds of torque and the intake manifold requires 30 foot-pounds of torque to bolt to the cylinder head. The rocker arm stud, which transfers radial movement to open the poppet valve, attaches to the cylinder head with 50 foot-pounds of torque.