What's The Difference Between Single And Dual Overhead Cam Engines?

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Camshafts are elemental devices, but important ones. Modern engines tin person 1 aliases much intake and exhaust valves, and it's nan camshaft's occupation to unfastened valves precisely arsenic nan motor runs, supplying nan aerial and substance required for soft and businesslike operation. The camshaft regulates nan opening and closing of nan valves utilizing lobes, aliases raised sections successful nan assembly. It turns successful sync pinch nan crankshaft, which is connected to nan pistons wrong nan motor block, via a timing loop aliases timing chain.

Many engines are commonly referred to arsenic overhead cam (OHC) engines, aliases those pinch camshafts connected apical of nan valves and combustion chamber. These types of engines are different from pushrods aliases overhead valve (OHV) engines, wherever nan camshaft is wrong nan motor block. Although location are still a fewer modern trucks you tin bargain pinch OHV motors, astir car engines characteristic OHC configurations pinch either azygous aliases dual camshafts.

The superior quality betwixt a single and dual overhead cam engine is nan number of camshafts wrong nan cylinder head. In a azygous overhead cam (SOHC) motor there's only 1 camshaft to govern nan intake and exhaust valves, while engines pinch dual overhead camshafts (DOHC) person two: One for nan group of intake valves and different for nan exhaust valves.

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There are pros and cons to SOHC and DOHC engines. Motors pinch a azygous overhead camshaft thin to person 2 aliases 3 valves per cylinder, but location are SOHC motors pinch 4 valves per cylinder. Despite having much restricted airflow, SOHC engines thin to nutrient much low- to mid-range torque. SOHC engines besides person less parts, which makes them much economical to manufacture and easier to repair. What's more, azygous overhead cam engines thin to measurement little acknowledgment to their simpler construction. Despite that, SOHC engines are constricted successful nan capacity stakes, but nan mid-range grunt makes them useful successful definite situations.

On nan different hand, engines pinch dual overhead camshafts (DOHC) typically person much analyzable designs and moving parts, making them costlier to manufacture and a spot trickier to disassemble and repair erstwhile thing goes wrong. And since DOHC motors person much parts, they are besides costlier to produce. However, astir DOHC engines person 4 valves per cylinder to amended nan airflow and volumetric efficiency, enabling them to nutrient amended horsepower and rotation faster. Moreover, DOHC makes it much feasible to merge variable valve timing technologies that alteration smaller engines to person much musculus while sipping little fuel.