TL;DR
- Twin scroll turbochargers help engines respond faster, reduce lag and use exhaust gases more effectively.
- A twin scroll turbo uses two separate exhaust paths so gases do not clash, helping the turbo spin quicker and deliver smoother power.
- The system includes a divided turbine housing, paired exhaust manifold runners, turbine and compressor wheels, a center housing rotating assembly and a wastegate to control pressure.
- Exhaust gases hit the turbine in a cleaner flow, allowing boost to build earlier, stay controlled and deliver power smoothly.
- Twin scroll turbos improve low-speed power, fuel use, emissions and allow smaller engines to perform better without strain.
- A twin scroll turbo suits cars that need smooth driving in daily use, while still offering strong power when required.
A Complete Guide to Twin Scroll Turbochargers
Turbochargers are essential components in modern engines, designed to increase power and efficiency by forcing more air into the combustion chamber. However, not all turbos perform the same way. The twin scroll turbo stands out as a more advanced design that is engineered to optimize exhaust flow and reduce turbo lag. By separating exhaust pulses from different cylinders, it improves responsiveness, increases torque at lower RPMs, and enhances overall engine efficiency.
In this turbo kit guide for twin scroll turbo, we’ll break down the mechanics of a twin scroll turbo, explain its unique design, and explore why it’s becoming increasingly important in performance and everyday vehicles.
What Is a Twin Scroll Turbo?
A twin scroll turbo is a type of turbocharger designed to improve engine efficiency, power delivery and throttle response. Instead of feeding all exhaust gases into a single turbine housing, a twin scroll turbo separates exhaust pulses from different cylinders into two distinct channels. This separation reduces exhaust-pulse interference and helps you achieve faster turbo spool-up with smoother power across the RPM range. The result is better low-end torque without sacrificing high-end performance, making your engine feel more responsive and balanced.
What Are the Key Components of a Twin Scroll Turbo?
Below are some of the key components of a twin scroll turbo:
- Divided Turbine Housing: Keeps exhaust pulses separate, allowing the turbo to spool faster.
- Paired Exhaust Manifold Runners: Send exhaust from matched cylinders into each scroll. This keeps the airflow smooth.
- Turbine Wheel: Spins from exhaust flow and powers the turbo.
- Compressor Wheel: It draws in air and compresses it to increase power.
- Center Housing Rotating Assembly (CHRA): Holds the shaft and bearings. It keeps everything spinning smoothly.
- Wastegate: Regulates boost pressure by diverting excess exhaust gas.
How Does a Twin Scroll Turbo Work? Step-by-Step Breakdown
Here’s a step-by-step breakdown of how a twin scroll turbo works:
Step 1: Exhaust Gases Enter Separate Channels
Your engine sends exhaust gases from specific cylinders into two separate paths. This keeps exhaust pulses from interfering with each other. Cleaner pulses mean better energy delivery to the turbo.
Step 2: The Turbine Spools Faster
Each exhaust pulse hits the turbine with more force. This helps the turbine spin faster at lower RPMs. Thus, increasing throttle response speed with reduced turbo lag.
Step 3: The Compressor Builds Boost
As the turbine spins, it drives the compressor wheel. The compressor pulls in fresh air and compresses it.
Step 4: Boost Pressure Is Regulated
The wastegate controls how much exhaust reaches the turbine. This keeps boost levels stable and safe. Your engine stays protected under load.
Step 5: Power Is Delivered Smoothly
Because airflow stays balanced, power builds smoothly. You get better low-end torque and strong top-end performance. The result is a responsive and efficient driving experience.
Also Read: Step by Step Instructions to Install Different Types of Turbo
Why Twin Scroll Turbos Are Important in Modern Engines
Below is the significance of using a twin scroll turbo in modern engines:
1. Improved Low-End Performance
Modern engines need to deliver power quickly. A twin scroll turbo helps you deliver strong torque at low RPMs by reducing lag and improving throttle response. This makes everyday driving smoother and more enjoyable.
2. Better Fuel Efficiency
By separating exhaust pulses, the turbo uses energy more efficiently. Your engine burns fuel more cleanly. This helps improve fuel economy without compromising performance.
3. Reduced Emissions
Cleaner combustion leads to lower emissions. Twin scroll turbos help engines meet stricter emissions standards. You get better performance while staying environmentally compliant.
4. Smoother Power Delivery
Power builds in a more controlled way. You avoid sudden surges or flat spots. This creates a balanced driving experience across the RPM range.
5. Supports Smaller Engines
Manufacturers rely on turbocharging to downsize engines. A twin scroll turbo allows smaller engines to produce more power. You get strong performance with less weight and better efficiency.
6. Ideal for Daily and Performance Driving
Twin scroll turbos work well in both daily drivers and performance cars. You get responsiveness in traffic and power when you need it. This versatility makes them essential in modern engine design.
Is a Twin Scroll Turbo Right for You?
A twin scroll turbo could be a smart choice if you’re looking to maximize your engine’s potential in a modern setup. It’s particularly useful for engines designed to deliver smooth power under a variety of conditions, from city driving to highway cruising. Because of its design, it can help your engine maintain stable boost and consistent airflow. Further, you’ll notice better drivability in situations where precise throttle control matters.
That said, twin scroll turbos are often best suited for cars where performance and engine efficiency are priorities.
Also Read: Types of Turbo Kits: Advantages and Disadvantages
Conclusion
A twin scroll turbo enhances engine performance by reducing lag, improving low-end torque, and delivering smoother, more consistent power. Its design allows engines to respond quickly across the RPM range while maintaining efficiency and reliability.
Since 1977, Diesel Components, Inc. has been helping engine owners get the most out of their equipment by providing high-quality diesel engine parts and expert guidance on performance upgrades like twin scroll turbos. With our reliable components, diagnostics, and support, we ensure your engines run efficiently, deliver smooth power, and stay protected from costly damage.
Don’t wait for performance issues to slow you down. Contact our team today and keep your equipment running at peak performance.
Call us: (800) 252-6625 | (952) 890-2885
Email us: sales@dieselcomponentsinc.com
FAQs
Q1. How is a twin scroll turbo different from a single-scroll turbo?
Ans. A twin scroll turbo uses a divided turbine housing and exhaust manifold to separate exhaust pulses. On the contrary, a single-scroll turbo combines all exhaust gases into one path, which can increase lag and reduce efficiency.
Q2. Does a twin scroll turbo reduce turbo lag?
Ans. Yes, one of the primary advantages of a twin scroll turbo is reduced turbo lag, especially at low engine speeds, due to improved exhaust pulse energy delivery to the turbine.
Q3. Is a twin scroll turbo the same as a twin turbo?
Ans. No. A twin scroll turbo is a single turbocharger with two exhaust gas inlets, whereas a twin turbo setup uses two separate turbochargers.
Q4. Do twin scroll turbos increase horsepower?
Ans. Twin scroll turbos can improve horsepower and torque by increasing turbo efficiency, but their biggest gains are typically seen in low- and mid-range torque rather than peak power.
Q5. Are twin scroll turbos only used in performance cars?
Ans. No. Many modern passenger vehicles use twin scroll turbos to improve fuel efficiency, emissions, and everyday drivability, not just performance.
