Turbo technology – one of the most popular and efficient ways to increase engine power in the modern automotive world. It allows for higher power output and more efficient fuel usage, which is why more and more drivers and enthusiasts are choosing various types of turbochargers for both sport tuning and everyday driving. One of the most important aspects when deciding on the optimal turbocharger is the pressure level, also known as boost. The two main categories are Low Boost and High Boost turbochargers. In this article, we will take a detailed look at what lies behind these names, their advantages and disadvantages, and when to choose one or the other.
Although the exact pressure limit that defines Low Boost or High Boost depends on the specific engine design and manufacturer specifications, generally Low Boost is associated with pressures up to around 7–10 psi (0.5–0.7 bar), while High Boost can go well above 15 psi (1 bar) and even exceed 30 psi (2 bar) in extremely powerful setups. Of course, these pressure ranges are approximate, but they help to better understand the general concept and distinguish the most important operating principles.
Low Boost turbochargers are often chosen when a slight but noticeable increase in engine power is desired without putting too much stress on the engine components. This can be an ideal solution for those who are just starting their tuning journey or simply want to add a bit of dynamism without dramatic modifications.
High Boost turbochargers, as the name suggests, are characterized by higher compression levels, which means more air enters the engine's combustion chamber, and more fuel is used accordingly. This combination creates significantly more power, but the installation and operation of such systems require much more attention.
The choice between Low Boost and High Boost often depends on the goals you have set for your car's tuning. If you have a daily driver and are looking for a slight but noticeable power increase while maintaining factory reliability, a Low Boost turbo can be a great solution. It will increase dynamism but won't require significant internal engine upgrades.
On the other hand, if you are a professional tuner, a drag racing or time attack enthusiast, and are aiming for maximum performance, choosing a High Boost turbo will be much more logical. In this case, you need to consider that significant investments will be required in the engine's internal components, ECU reprogramming, exhaust system, ignition system, and even fuel quality (often higher octane fuel or even E85 mixtures are used).
Low Boost turbos usually require timely oil changes, filter replacements, and ensuring that the intercooler system is not leaking, and the engine cooling system is functioning properly. Such cars can often be driven daily without worries if all engine parameters are properly tuned.
High Boost systems require much more meticulous maintenance. Increased pressure creates higher thermal loads, so higher-quality oils and more frequent oil changes are necessary. The installation and monitoring of various sensors (e.g., wideband lambda sensors, EGT sensors) are almost mandatory to monitor the mixture composition, exhaust gas temperature, and avoid potential engine overheating or detonation issues.
With the rapid advancement of turbocharger technologies, there are more and more ways to reduce turbo lag while maintaining high boost levels. One such solution is the electric compressor, which can provide instant airflow while the larger turbo spools up to operating speed. Additionally, hybrid technologies allow electric motors to take on part of the load in the overall system management, simplifying the adaptation of high boost turbos even in everyday vehicles.
Low Boost and High Boost turbochargers – two fundamentally different approaches to improving engine power. Low boost systems offer a balanced power increase, often ensuring minimal risk and simpler maintenance, making them popular among beginner tuning enthusiasts and daily drivers. High boost turbos, on the other hand, offer the opportunity to achieve significantly higher power levels, but they require careful selection of internal engine components, fuel systems, cooling systems, and often come with higher operating costs and more frequent maintenance.
In the end, it's important to note that both Low Boost and High Boost solutions can serve well in various car engine platforms – the choice depends on financial resources, goals, and the ability to implement additional structural or electronic measures. Some are satisfied with a slight power increase that ensures daily comfort and reliability, while others need maximum traction and impressive results on the racetrack. No matter which option you choose, a properly maintained and balanced turbocharger system can be a great way to give your car a unique character and significant power reserve.