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Dual Overhead Cam (DOHC) refers to an engine configuration where two camshafts are situated above the cylinder head to operate the intake and exhaust valves separately. This design contrasts with Single Overhead Cam (SOHC) engines, where a single camshaft controls both the intake and exhaust valves using different lobes on the same camshaft.
Key features of DOHC engines include:
- Camshaft Configuration: DOHC engines have one camshaft dedicated to operating the intake valves and another for the exhaust valves. This setup allows more precise control over valve timing and lift compared to SOHC engines.
- Efficiency and Performance: DOHC engines are generally more efficient and capable of higher performance levels due to their ability to optimize valve timing for both intake and exhaust cycles independently.
- Complexity: While DOHC engines offer superior performance, they are more complex and can be more challenging to manufacture and maintain. Adjusting the valves, for example, typically requires more effort and precision compared to SOHC engines.
- Variants: DOHC engines are also referred to as Double Overhead Camshafts, Twin Overhead Camshaft engines, emphasizing their dual camshaft design.
DOHC engines are favored in applications where performance and efficiency are paramount, such as in sports cars, high-performance sedans, and some motorcycles. They offer advantages in terms of power output and flexibility in tuning, albeit with increased complexity in design and maintenance.
See
- Engine type