DOHC 16V – What is a DOHC 16 Valve Engine?

One of the most important aspects to consider in a vehicle’s engine is air and fuel distribution into its combustion chamber. The smoother this distribution happens, the better.

You probably already know that the component that distributes the gas in the engine is the valve. But have you ever heard of the DOHC engine?

In this post, I’ll walk you through everything you need to know about the DOHC 16v engine or otherwise known as the Dual Overhead Camshaft 16 valve engine.

But first, let’s look at how a car engine works.

DOHC 16 valve engine

How A Car Engine Works

At a high level, a gasoline engine can be thought of as somewhat like an air pump, except that the exhaust coming out is more of a side effect.

This pump’s real purpose is to rotate an internal shaft which in turn rotates the vehicle’s wheels.

It does this by connecting that shaft – called a crankshaft to pistons that move due to a mixture of air and gasoline combusting inside their cylinders, which creates a sort of chain reaction that keeps the engine turning.

The two main parts of an engine are the Block and the Head. The Block, which is at the bottom is home to the pistons, cylinders, and crankshaft. The crankshaft sends the engine’s power out to the transmission and wheels.

The head which is above contains the top of the cylinders and manages their airflow and combustion through valvetrain, fuel injection, and ignition systems. You can see this post to learn about a particular type of head – the 862 LS heads.

What is DOHC 16V?

DOHC 16v refers to a 4-cylinder internal combustion engine with 4 valves in each cylinder and two camshafts.

The reason for the use of two camshafts is that the engine uses four valves in a cylinder – 2 valves for the intake and the other 2 valves for the exhaust.

As a result of this number of valves, the air distribution is faster so that the engine RPM can easily reach its maximum.

A camshaft is driven by the crankshaft of the engine and it opens the intake and exhaust valves so that the engine can take air in and expel the exhaust gases. It is installed on the cylinder head so that it will directly press the valve.

In some types of DOHC 16v engines, Rocker Arms are used in adjusting the valve gap. DOHC mechanisms that use Rocker Arms have a hydraulic lash adjuster system to automatically adjust the valve gap.

For those without Rocker Arms, the valve gap is adjusted manually using a ring that is placed inside the valve lifter. To change the valve gap, this ring must be replaced.


Both SOHC and DOHC represent the valve configuration inside an engine head to control the action of the valves. Though these configurations are renowned for their superior performance, both have some significant differences.

SOHC stands for single overhead camshaft. This type of valve configuration utilizes only a single camshaft for operating both intake and exhaust valves.

DOHC or dual overhead camshaft on the other hand utilizes two independent camshafts for the operation of the intake and exhaust valves.

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FAQs on DOHC 16v Engine

What Does 16v Mean in a Car?

The term “16v” in a car typically refers to the engine’s valve train configuration. It specifically means that the car has a 16 valve engine. These valves control the flow of air and fuel into and out of the combustion chambers.

In contrast, an engine with an 8v designation would only have 8 valves, while a 24v engine would have 24 valves. The more valves an engine has, the more efficiently it can breathe, which can lead to improved performance and fuel economy.

It’s worth noting that while valve count is one factor that can impact an engine’s performance, it’s not the only one.

Other factors, such as cylinder count, displacement, and forced induction, can also play a role in determining how powerful an engine is.

Is a 16 Valve Engine a 4 Cylinder?

A 16 valve engine is not necessarily a 4 cylinder. The number of valves an engine has is not directly related to the number of cylinders it has.

A lot of 4-cylinder engines have 16 valves. However, there are also 4-cylinder engines with fewer valves, such as 8 or 12 valves.

Similarly, there are engines with more than 4 cylinders that have 16 valves, such as some V6 or V8 engines.

The valve count is determined by the engine designer’s goal to optimize the engine’s performance. This is influenced by several factors such as combustion chamber shape, piston design, and fuel delivery systems.

Ultimately, the design and configuration of an engine depend on its intended application and the goal of the manufacturer.

Is a DOHC 16v Engine Good?

Yes, a DOHC 16v engine can be good, depending on its design, specifications, and application.

Generally, DOHC engines offer better performance than single overhead camshaft (SOHC) engines because they have separate camshafts for the intake and exhaust valves. This allows for greater control over valve timing and better airflow.

The 16-valve configuration also means that there are four valves per cylinder, which can help the engine breathe better and produce more power.

However, the quality and reliability of a DOHC 16V engine depend on many factors, including the materials used, the manufacturing process, and the maintenance history.

In addition, the engine’s specific output, fuel efficiency, and durability can vary depending on the size, type, and intended use of the engine.

How Many Cylinders is a 16 Valve Engine?

The number of cylinders in a 16 valve engine can vary depending on the specific design and manufacturer. The number of valves in an engine refers to the number of openings that allow fuel and air to enter the combustion chamber and exhaust to exit.

It does not necessarily indicate the number of cylinders in the engine.

For example, a 16 v engine could be a four-cylinder engine with four valves per cylinder, or it could be a six-cylinder engine with two valves per cylinder. Some engines may also have more than four valves per cylinder, such as five or even six valves per cylinder.

Therefore, without additional information about the specific engine in question, it is not possible to determine the number of cylinders in a 16 valve engine.


The DOHC 16v or Dual Overhead Camshaft 16v is an internal combustion engine type with a 4-valve mechanism within the 4 cylinders – making up a total of 16 valves.

It is different from the SOHC or Single Overhead Camshaft in the sense that it has two camshafts while the SOHC has just one camshaft.