What is DOHC?

[DelRiver]

DOHC is a type of automobile engine. Generally, a DOHC engine has higher torque and power compared to a regular engine. The most significant feature is that it is a TWIN-CAM, which typically delivers about 15% more horsepower than a standard engine. The pistons in a DOHC engine are also different from those in a regular engine, as they need to be more robust to maintain normal engine operation. Additional details are as follows: 1. DOHC: As the name suggests, it stands for Double Overhead Camshaft. From the working principle of an engine, it is understood that a complete cycle includes intake, compression, combustion, and exhaust. To achieve intake and exhaust, the cylinder requires intake and exhaust valves, and the camshaft's role is to mechanically coordinate the opening and closing actions of these valves. 2. SOHC: Refers to a setup where a single camshaft controls the opening and closing of both intake and exhaust valves, whereas DOHC uses two separate camshafts to control the intake and exhaust valves independently. The advantage of DOHC is that it allows easy adjustment of the valve timing, enabling the engine to deliver ample torque at low RPMs and maximum horsepower at high RPMs. Typically, high-performance, large-displacement engines often use DOHC. DOHC does not increase fuel consumption; instead, it allows the engine to perform more efficiently.

[DawsonLee]

DOHC stands for Double Overhead Camshaft, which is a common engine design. I often come across this technology when playing racing games. It features two camshafts, one dedicated to controlling the intake valves and the other managing the exhaust valves, allowing for more precise valve timing compared to older single camshaft engines that required components like rocker arms. This design enables the engine to run more smoothly at high RPMs, increases power output, and also helps improve fuel efficiency due to more complete combustion. My own car uses DOHC, and it feels incredibly smooth when driving, with much quicker throttle response. In terms of maintenance, DOHC can be slightly more demanding—for example, the timing chain needs regular checks—but overall reliability is good; I’ve driven mine for five years without major issues. If you’re looking to buy a new car, check if the engine model includes this abbreviation, as it delivers a more enjoyable driving experience.

[DiPreston]

When it comes to car engines, I've worked on quite a few DOHC machines. It actually uses two separate camshafts in the cylinder head to independently operate the intake and exhaust valves, eliminating the complexity of older designs. This system is particularly common in high-performance cars because it allows for more precise valve timing, enabling the engine to breathe better and naturally increasing horsepower output. During oil changes and inspections, I always remind owners to pay attention to camshaft chain wear to prevent power loss caused by skipped teeth. In terms of fuel economy, DOHC engines typically save some fuel as precise valve control reduces energy waste. Compared to single camshaft engines, they're quieter, have less vibration, and are more comfortable for long-distance driving. However, initial repairs might be slightly more expensive as they require specialized tools, so I recommend a comprehensive annual maintenance check. Overall, it's a good choice, especially for drivers who enjoy performance.

[OMason]

I have some basic knowledge about cars. Simply put, DOHC means there are two shafts at the top of the engine to control the opening and closing of valves. My family car uses this, and it runs quietly with smooth acceleration. It's more fuel-efficient than older models, saving a bit of fuel per 100 kilometers because the engine operates more efficiently. For maintenance, I usually just change the oil on time, and there's not much trouble. This design can be found in most new cars, with high reliability, and it's less prone to malfunctions even after long-term use.

[FinnDella]

When driving a sports car, DOHC is my favorite part—it directly boosts engine performance. The twin-camshaft design delivers ultra-responsive valve action, eliminating lag during acceleration, especially in high-speed cornering or sprints, where power delivery becomes even fiercer. Compared to single-cam engines, it maintains steadiness near the redline, burns fuel more cleanly, and wastes no power. In my racing experience, DOHC cars offer greater tuning potential, making it easier to achieve higher peak outputs. However, maintenance requires careful attention to the timing chain to prevent slack-related issues. Overall, it’s a brilliant engineering touch that elevates driving excitement.