Why Does the Automotive Intercooler Cause Turbo Lag in Turbocharged Engines?
In principle, the larger the design of the car intercooler, the smaller the air loss inside, and the higher the cooling efficiency. And the longer the airflow stays in the car's intercooler, the better the final cooling effect. In reality, when air enters the car's intercooler, this space needs to be filled first, and then the pressure can continue to be output to the engine cylinder.
Ⅰ. Why does the automotive intercooler cause turbo lag?
1. Filling time
The power source of the turbine is the conversion of exhaust gas. The higher the speed, the more exhaust gas is produced. The intake pressure is also stronger. If the throttle is loosened, the amount of air required by the engine is drastically reduced, causing the intake pressure to be too high, and the pressure will leak and damage the intake system. So when you reduce the throttle, there will be a pressure relief valve to drain the excess air pressure and then build pressure to intervene when you need the turbine.
Therefore, even a supercharged car will experience a slower engine response. Car radiator manufacturers are mainly doing the tuning, which is equivalent to putting part of the energy into the delay adjustment of the car's intercooler.
2. Air entering the cylinder will cause the air pressure to be partially diluted
This dilution is mainly produced after a short period after the accelerator is stepped on and the turbo intervenes. If you do not step on the accelerator, in order to maintain the safety of the engine boost system, the pressure relief valve will be opened and the intake pressure will be emptied.
So while you are refueling, this part of the enclosed space from the car's intercooler to the intake valve needs a buffer time to re-establish sufficient air pressure. So, in the end, the performance for the car owner is a slow response, referred to as turbo lag.
At present, the solutions of automobile radiator manufacturers are to shorten the intake pipeline as much as possible, so the car intercoolers we often see are close to the engine and are attached.
Especially those high-end, large-displacement engines require a greater intake of air. If it is not enough, its temperature will be higher, so a large car intercooler will be installed. These containers are usually placed on the top of the engine. The advantage is that you can open an air inlet in the engine compartment to divert the low-temperature air outside and hit the car intercooler to cool down. This setting can be seen in many models.
Ⅱ. The benefits of placing the car intercooler above the engine
1. The advantage is that the structure is compact, and the pipeline is relatively short. If you want to use it in your car modifier, it is more suitable for small cars and saves space. The problem is that this type of layout may be affected by engine temperature because it is close to the engine.
2. Of course, another layout is to place the engine car intercooler in the front center grid of the car to obtain a larger area of air-cooled heat dissipation. However, because the pipeline is complex and lengthy, it is mainly used in mid-to-high-end cars. There are also quite a few cars that use coolant to cool the intake air temperature.