How does an overhead cam (OHC) engine differ from a pushrod engine?

How does an overhead cam (OHC) engine differ from a pushrod engine?

• A. OHC engines are more powerful
• B. OHC engines have the camshaft above the cylinders
• C. Pushrod engines are more efficient
• D. Pushrod engines operate at higher RPMs

Answer: (B)

An overhead cam (OHC) engine is characterized by its camshaft positioning, which is located above the engine's cylinders. This design allows for more direct control over the timing of the valves, as the camshaft can operate more efficiently in a vertical position compared to a pushrod engine, where the camshaft is located in the engine block. The direct placement of the camshaft in an OHC engine often contributes to better airflow into and out of the combustion chambers, ultimately improving engine performance, allowing for advanced timing systems, and facilitating the use of multiple valves per cylinder. This can lead to increased horsepower and efficiency compared to traditional pushrod configurations, where additional components like pushrods and rocker arms may introduce more complexity and potential energy losses. Understanding this design differentiation is essential when discussing engine technology and performance characteristics, as it highlights the architectural advancements that OHC engines have over traditional pushrod designs.

An overhead cam (OHC) engine is characterized by its camshaft positioning, which is located above the engine's cylinders. This design allows for more direct control over the timing of the valves, as the camshaft can operate more efficiently in a vertical position compared to a pushrod engine, where the camshaft is located in the engine block.

The direct placement of the camshaft in an OHC engine often contributes to better airflow into and out of the combustion chambers, ultimately improving engine performance, allowing for advanced timing systems, and facilitating the use of multiple valves per cylinder. This can lead to increased horsepower and efficiency compared to traditional pushrod configurations, where additional components like pushrods and rocker arms may introduce more complexity and potential energy losses.

Understanding this design differentiation is essential when discussing engine technology and performance characteristics, as it highlights the architectural advancements that OHC engines have over traditional pushrod designs.