Car enthusiasts are always looking for ways to improve their vehicle’s performance. While at first you may be satisfied with a simple turbo upgrade, you may soon find yourself seeking further boosts. With numerous ways you can increase your engine’s power and vehicle speed above its average, many turn to using anti-lag systems. So, what is turbo anti lag and how does it affect your overall vehicle performance?
In this article, we’ll explain the meaning behind turbo lag and how these anti-lag systems aim to break its limits. By elaborating on the use and functions of turbo anti-lag, you’ll have a better understanding of the advantages and disadvantages of these systems. Furthermore, we’ll cover the legal aspect of using turbo anti lag and the most common systems used.
Continue reading to discover what is anti lag system and how it influences your vehicle’s performance!
Source: shutterstock.com / Photo Contributor: Rosen Vasilev
What Is Turbo Lag?
Before we elaborate on the use of anti-lag systems, we first want to explain what turbo lag actually is. In simple terms, this effect portrays the delay that happens between the moment the driver accelerates their vehicle by opening the throttle and the moment they feel the boost from their turbo. Since the turbocharger must compress the air entering the engine to successfully increase its power, it can take some time until it reaches the needed boost pressure.
Furthermore, turbochargers use exhaust gasses to spin the turbine. So, while the turbo builds up the necessary exhaust pressure, the vehicle isn’t getting the desired power boost. This action leads to a short-term lack of response, especially noticeable when shifting from a lower gear or during rapid acceleration.
While the turbo lag may naturally increase over time, its main causes are the following:
- Turbo system design
- Throttle and airflow response
- Compressor and turbine matching
- Turbo size and inertia
- Faulty wastegates
- Exhaust flow
What Is Turbo Anti Lag?
Now that you understand the basics behind turbo lag, we want to elaborate on how turbo owners aim to combat it with anti-lag systems. As the name implies, an anti-lag system is used to reduce or eliminate turbo lag by making adjustments that allow the turbocharger to keep moving even when the engine slows down. It’s often referred to as ALS (anti-lag system) and is most commonly used in performance vehicles and motorsports, such as Formula One. By keeping the turbocharger engine pressurized and spinning, you can feel the horsepower and boost as soon as you step on the gas.
How turbo anti-lag systems work
So, how does this anti-lag system work to reduce the dreaded turbo delay? First, remember that diesel turbos require exhaust gasses to keep the turbine spinning. Instead of losing speed when the throttle is closed, antilag systems maintain boost pressure even during low-power moments.
As with many vehicle upgrades, there are different types of turbo anti-lag systems you can choose from. So, anti-lag systems work in different ways depending on their type. To better understand their function, we’ll elaborate on the most common ALS systems, such as the following:
- Throttle bypass
- Secondary air injection
- Ignition retard
Throttle bypass
The first type of ALS is known as a throttle bypass. As the name implies, this anti-lag system allows air to keep flowing within the engine even while the throttle is closed because the throttle plate is kept slightly open. This is done by installing a bypass valve that’s controlled by the vehicle’s ECU (engine control unit). The continuous airflow into the engine ensures that exhaust gasses keep flowing, maintaining the speed of the turbocharger.
Secondary air injection
The second type of anti lag system you can try out is known as a secondary air injection. Also known as a rally-style ALS, this advanced technique injects air directly into the exhaust manifold during deceleration to keep the turbocharger spinning. This method requires you to add a plumbing mechanism before the throttle plate, which diverts the air around the engine and feeds it to the exhaust manifold.
Two additional elements of this anti-lag system are the bypass valve that controls the flow of diverted air, and the ECU used to control the rich fuel mixture during deceleration. The mixture of extra air, unburnt fuel, and high-temperature exhaust gasses leads to secondary explosions that keep the turbo working.
Ignition retard
The last type of anti-lag system we’ll cover is the ignition retard. It involves delaying the ignition timing and enriching the fuel mixture to operate the turbo more efficiently. This technique requires a programmable engine control unit (ECU) to adjust the ignition during gear shifts. Since it acts as a quick spool system, it helps the turbocharger reach the optimal boost pressure as fast as possible.
Is Anti Lag Illegal?
The main question many turbocharger enthusiasts have is whether are anti-lag systems illegal. Even though ALSs are commonly used in motorsports and racecars, their legal status for street use depends on local laws and regulations. The two main regulation standards you should be wary of are the emissions and noise regulations. Many anti-lag systems create excess unburnt fuel in the exhaust, which can result in increased emissions.
Furthermore, ALSs are known to be quite loud due to the combustion and backfiring in the exhaust system. If your local laws have strict regulations for these standards, using such a turbocharger on the streets can lead to fines and penalties.
Source: shutterstock.com / Photo Contributor: Stason4ik
Pros and Cons of Turbo Anti-Lag System
We want to highlight the advantages and disadvantages of installing a turbo anti-lag system. To get a better understanding of its effects, we’ll cover both the pros and cons separately.
Pros of turbo anti-lag systems
The main benefits of using an anti-lag system for your turbocharger are the following:
- Improved acceleration
- Instant throttle response
- Increased boost pressure
- Sustained power during gear shifts
Cons of turbo anti-lag systems
While installing an anti-lag system may seem appealing, it’s essential to consider its disadvantages. The primary concern is the potential damage it can cause to your vehicle’s engine. Here are the main drawbacks to keep in mind:
- Increased emissions
- Higher fuel consumption
- Increased heat and overheating risks
- Increased wear on engine components
- Legal restrictions
Conclusion
What is turbo anti lag, and how does it affect your vehicle's performance? Since these systems are specifically designed to combat the dreaded turbo lag, they involve various adjustments to keep the turbo running even when the engine has slowed down. Even though there are various types of ALS you can try out, their main function is to keep the turbo spinning even when the throttle is closed.
Before you decide to install such systems, we advise you to check your local laws and regulations to ensure they don’t interfere with emission and noise standards. Lastly, carefully consider both the pros and cons of turbo anti-lag systems because they can potentially damage your engine and lead to increased risks of overheating.
