Third generation Vortec engines that include models LM7, L59, LM4 and L33 feature cylinder heads made of cast aluminum. All the engine models in the generation have two valves in each cylinder and are supplied with fuel using a sequential fuel injection system. Models LM7 and L59 have a compression ratio of 9.5 to one; model L33 features a ratio of 9.6 to 1.Continue Reading
Fourth generation Vortec engines includes models LH6, LY5, LMG, LC9 and LH8. Cylinder heads of models LMG and LC9 are made of cast aluminum. However, the block of the LMG engine model is made of cast iron, while the block of the LC9 is also made of cast aluminum. The ignition system of both models consists of a coil near plug, platinum-tipped spark plugs, composite distributor and low-resistance spark plug wires. The LMG model features two separate fuel delivery systems, including the active fuel management and the sequential fuel injection system, while the LC Vortec engine model comes only with the sequential fuel injection system.
The L33 Vortec engine offers drivers 310 horsepower and a torque of 335 pounds per foot. The LM7 Vortec model produces 270 horsepower and a torque value of 315 pounds per foot. All engine models in both generations have a capacity of 325.1 cubic inches, a bore that is 3.78 inches long and a stroke that measures 3.622 inches.Learn more about Engine