Of turbochargers

Types of Turbochargers

Turbos are used in almost all modern vehicles due to their fuel efficiency and improved performance. They compress the air that flows into the engine, so it burns more fuel and generates more power. There are several types of turbochargers designed to meet specific needs.

• Variable geometry turbocharger: VGTs are commonly used in diesel engines. They have adjustable blades that change position depending on the engine speed. This improves performance at low RPMs and reduces turbo lag. VGTs also improve fuel efficiency and emit fewer pollutants. However, these turbochargers are more expensive and require more maintenance.
• Variable twin-scroll turbocharger: VTTs are a combination of VGT and VTG turbochargers. They are suitable for high-performance petrol engines. The variable geometry mechanism in the VTT helps to eliminate turbo lag and boost the engine's response. This turbo is pricier than the VGT, so it's mainly used in supercars.
• Wastegate turbocharger: WG turbos are the most common types of turbochargers. They are affordable and low maintenance, making them popular among car owners. WG turbochargers use wastegates to control the boost pressure produced by the turbo. They have a simple design and are mainly used in naturally-aspirated petrol engines.
• Electric turbo-compound: ETC is a new technology being adopted in modern vehicles. It uses an electric motor to drive the turbine and generate more boost. This eliminates lag and provides a constant boost across the entire engine's RPM range. ETCs are often used in hybrid and electric vehicles due to their energy-saving abilities.
• Single and twin turbochargers: Single turbochargers are the most common types. They use a single turbine to compress the exhaust. Twin turbines are used in twin turbochargers, which result in faster spool times and more power. Some high-performance vehicles come with factory-installed twin turbochargers. They are also added to naturally aspirated engines to significantly improve performance.
• Bi-turbo and sequential turbochargers: Bi-turbos work with two turbochargers, often configured in a single or twin layout. They are commonly used in V6 and V8 engines. Sequential turbos are two turbochargers of different sizes. The smaller one spools quickly to boost low-end torque, while the bigger turbo kicks in at high RPMs to provide a broader power band.

Specifications and maintenance of turbochargers

Specifications of turbochargers vary by type and design. Here are some general specifications:

• Compressor

  Compressor Wheel: The compressor wheel draws air into the turbo and compresses it before sending it to the engine. It is measured in inches or millimeters. A larger wheel results in more airflow and pressure but requires more power to spin it. A smaller wheel requires less power to spin but provides less airflow and pressure. The size is a trade-off.

• Turbine

  Turbine Wheel: The turbine wheel is spun by exhaust gases from the engine. It is also measured in inches or millimeters. A larger wheel results in more power being drawn from the exhaust but requires more work from the engine to spin it. A smaller wheel requires less effort from the engine but pulls less power from the exhaust. The size is a compromise.

• Bearings

  Journal Bearings: These bearings support the shaft between the compressor and turbine wheels. They reduce friction and allow the shaft to spin smoothly. The size and material of the journal bearings affect how quietly and efficiently the turbocharger operates.

• Wastegate

  Actuator: The wastegate actuator controls how much exhaust flows through the wastegate. It is powered by a spring or vacuum and regulates boost pressure. The wastegate actuator's size and strength affect how precisely boost pressure is managed.

• Blow-off valve

  Spring: The blow-off valve spring controls how quickly the valve opens and closes when boost pressure changes. A stiffer spring results in more resistance and slower valve action. A softer spring allows for faster blow-off of excess pressure.

The maintenance of turbochargers is straightforward. Here are some maintenance tips:

• Regular oil changes: Clean oil helps the turbo get enough lubrication. Change the oil every 5,000 to 7,500 miles (8,000 to 12,000 km) or as recommended. Use oil with the right viscosity rating the manufacturer suggests. This protects the turbo from damage and keeps it running smoothly. Synthetic oil is good for the turbo because it lasts longer and protects better in high temps.
• Letting the turbo cool: Before turning off the engine, let it idle for a minute. This gives the turbo time to slow down. The heat from the hot turbo can burn the oil if the engine is turned off right away. The burnt oil can clog the turbo and make it work poorly. Idling for a minute or using a turbo timer allows the turbo to cool safely.
• Using the right tune: Follow the manufacturer's tune specs for the turbo model. A tune with too much boost or too lean of an air-fuel ratio can stress the parts. This causes the turbo to wear out faster. Get a tune with the correct settings and proper airflow to keep the turbo healthy over time. This ensures it performs at its best.

How to choose of turbochargers

It's no secret that turbochargers are in high demand, and many people want to know how to choose the right one. Some of the factors to consider when choosing a turbocharger are:

• Engine Size

  When selecting a turbocharger, the engine size has to be considered. This is because the engine size determines the power output of the vehicle. Larger engines generate more power and require bigger turbochargers to produce the desired boost. On the other hand, smaller engines generate less power and require smaller turbochargers.

• Driving Style

  Driving style has to be considered when choosing a turbocharger. Drivers that have a more aggressive driving style will need a bigger turbocharger to meet their power demands. Contrarily, a smaller turbocharger is sufficient for drivers with a more relaxed driving style.

• Type of Turbocharger

  Different types of turbochargers are available to suit various applications and requirements. For instance, variable geometry turbochargers (VGTs) are perfect for diesel engines because they improve low-end torque and reduce turbo lag. Dual-scroll turbochargers are great for extracting maximum power from an engine by efficiently using exhaust gases.

• Budget

  There are various turbochargers on the market, and they come in different sizes and types. This means that there are also different price points. When choosing a turbocharger, the budget also has to be considered. It's important to find a balance between the desired performance and the amount willing to be spent.

How to DIY and Replace of Turbochargers

Replacing a turbocharger is no easy feat. It requires specialized tools, mechanical skills, and knowledge of the vehicle's engine system. Here is a step-by-step guide for replacing turbochargers:

• Gather all necessary tools for the replacement process. This includes sockets, wrenches, screwdrivers, a torque wrench, and possibly specialized tools for the specific vehicle make and model.
• Get the new turbocharger ready for installation. Ensure it is compatible with the vehicle's engine and meets OEM specifications.
• Disconnect the battery before starting any work on the vehicle's engine. This ensures safety and prevents any electrical damage or short circuits.
• Drain the engine oil and coolant to prevent any leaks or spills during the turbocharger replacement process.
• Remove the engine cover and any other components obstructing access to the turbocharger.
• Disconnect the turbocharger from the intake and exhaust systems. Depending on the vehicle's turbocharger design, this may involve removing bolts, clamps, and hoses.
• Disconnect the turbocharger from the oil and coolant lines. Again, this may involve removing hoses, clamps, and bolts.
• Once the old turbocharger is disconnected, carefully install the new turbocharger by reversing the steps of disconnection. Ensure all bolts, clamps, and hoses are securely fastened to prevent any leaks or loose connections.
• After installing the new turbocharger, reconnect the oil and coolant lines. Double-check for any leaks or damp spots and address them accordingly.
• Reconnect the turbocharger to the intake and exhaust systems. Ensure a snug fit and secure all connections to prevent any air or exhaust leaks.
• Replace the engine cover and any other components removed during the disconnection process.
• Refill the engine oil and coolant before starting the vehicle. Make sure to use the recommended fluids and quantities as specified in the vehicle's owner's manual.
• Reconnect the battery and start the vehicle. Allow it to idle for a few minutes to ensure the new turbocharger warms up and all systems function correctly.

Q and A

Q1: Are there any new technologies improving turbochargers?

A1: Turbochargers are evolving rapidly. They are developing new materials that can withstand the heat better and last longer. Also, they are changing the way bearings work to make turbines spin up faster. Some are even going electric to give instant power.

Q2: How often should a turbocharger be replaced?

A2: With proper care, a turbocharger can last around 100,000 to 200,000 kilometers. Signs of a worn-out turbo are slow spool-up, visible damage, or oil leaks. It is better to check the turbo regularly.

Q3: What causes turbo lag?

A3: Turbo lag happens when there's a delay in the turbo kicking in. It's caused by the exhaust not spinning the turbine fast enough. Lag can be reduced with tuning, changing the wastegate, or using variable geometry.

Q4: How does a variable Vane turbo work?

A4: It changes the angle of the blades inside the turbo. This helps catch more exhaust air, making it spin faster. Variable Vane turbos boost power without lag.

Q5: Are dual turbo systems better?

A5: Dual turbos can be more efficient. A smaller one spools up fast for low-end torque. A larger one kicks in for high speeds. It gives a smooth power band across the revs.