Twin Scroll Turbo vs Single Scroll Turbo: Which Is Better for Your Car?

When it comes to turbochargers for your car, there are two main types: twin-scroll and single-scroll. Both types have advantages and disadvantages, so it’s important to know which is better for your specific car and driving needs.

A twin-scroll turbo has two separate exhaust gas inlets and two corresponding turbine wheels, which work together to increase engine performance. On the other hand, a single scroll has only one inlet and turbine wheel. While a twin scroll turbo can provide quicker response times and better low-end torque, a single-scroll typically provides more top-end power. In this article, we will look at the differences between these two types of turbochargers and help you determine which one is best for your car.

How Twin Scroll Turbos Work?


Twin scroll models are designed to separate the exhaust gas pulses into two scrolls. That is achieved by using a turbine housing with two separate channels or inlets divided by a wall. The wall separates the exhaust pulses so that they do not interfere with each other and instead hit the turbine blades at different intervals. That allows for better energy utilization and faster spool-up times than single scroll.

The use of two separate scrolls allows for more efficient use of exhaust gas energy. By separating the exhaust pulses, each pulse can be directed to a separate scroll, resulting in less interference between exhaust pulses and less exhaust gas energy lost. That leads to better response and improved power output, especially at low engine speeds.

Advantages of Twin Scroll Turbos

This type of turbo offers several advantages over other options. One of the most significant advantages is improved low-end torque. The unique design allows for faster acceleration times and better energy utilization, improving low-end torque and drivability.

Another advantage of twin scroll is improved exhaust gas scavenging. Separating exhaust gas pulses into two separate scrolls results in better exhaust gas scavenging, reducing exhaust backpressure and allowing the engine to breathe more freely. That can lead to improved power output and better fuel economy.

How Single Scroll Turbos Work?


Single scroll turbochargers, also known as mono-scroll, use a turbine housing with a single inlet and exhaust gas outlet. The exhaust gases enter the turbine housing through the single inlet and hit the turbine blades, which drive the compressor wheel. The compressed air is then fed into the engine’s intake system.

While they are simpler in design compared to twin scroll models, they are less efficient at low engine speeds due to exhaust gas interference between exhaust pulses.

Advantages of Single Scroll Turbos

First of all, we have to mention that this option represents a cost-effective solution for boosting engine performance. It is simpler in design compared to twin scroll, which makes them less expensive to manufacture and maintain.

Another advantage is the compact size. The unique design allows for a smaller overall package, which is important in limited space applications. Additionally, these models can be more forgiving in terms of tuning and installation, making them a popular choice for aftermarket upgrades.

Factors to Consider When Choosing This Upgrade

There are several important factors to consider. One of the most important factors is the size and configuration of your engine. Larger engines may require larger upgrades to provide the necessary boost, while smaller engines may benefit from smaller ones that can spool up more quickly. Another important factor is your driving needs and preferences.

For example, if you prioritize low-end torque and quick acceleration, you may choose an option designed to provide a quick boost response. On the other hand, if you prioritize high-speed driving and top-end power, choose a turbocharger to provide a maximum boost at high RPMs. You should also pay attention to the availability of aftermarket parts and support, the reputation of the manufacturer, and your budget.

Installation and Maintenance

Proper installation and maintenance are essential to ensure reliable and long-lasting performance. Some key steps in installing and maintaining include following the manufacturer’s guidelines and recommendations, using high-quality oil and lubricants, inspecting and cleaning it regularly, and ensuring that it is properly calibrated and adjusted.

It is also important to be aware of potential issues, such as overheating, oil leaks, and damage to the bearings or seals. Regular inspections and maintenance can help to identify these issues before they become more serious.

Pros and Cons of Upgrading

Upgrading your turbo can significantly increase power, acceleration, and overall performance. However, there are also potential disadvantages, such as increased cost, potential warranty and insurance issues, and the need for additional modifications to support the new turbocharger.

Also, upgrading your turbocharger can place additional stress on other engine components, such as the pistons, rods, and valves, which may require additional upgrades or modifications to support the increased power output. This can be the case with both twin and single scroll models.

How They Improve Engine Performance?


They work by compressing air and delivering it to the engine, allowing it to burn more fuel and produce more power. This results in increased horsepower, torque, and improved acceleration and overall responsiveness. Turbochargers can also improve fuel efficiency by allowing the engine to produce more power with less fuel.

Because exhaust gases drive turbochargers, they do not require any additional energy input from the engine, which can improve overall efficiency and reduce stress on the engine. Additionally, turbochargers can be a cost-effective way to upgrade your engine’s performance, as they can provide significant power gains with relatively minimal modifications.

The Bottom Line

As you can see, there are many benefits related to both of these options. The key feature is that the twin scroll is offering more power. However, there are other details that will help you choose the right solution for the upgrade of your vehicle, such as the main goal, type of the car, and you budget.

In the end, these types of upgrades should always be done by experts. Therefore, be sure to consult with one before you start tuning your car.