Intercooler On Superchargers: Is It Really Required?

By December 2, 2021Intercooler, Turbocharger

Intercoolers are required for superchargers to ensure peak performance and longevity of your engine.

The compressed air coming from the supercharger is too hot for combustion – it has to be cooled by intercoolers first.

I, myself, have installed superchargers. With time, I have realized that intercoolers are truly necessary. 

I didn’t install it in the beginning as it doesn’t look badass. Well, I didn’t know there are a lot of thermodynamic tricks going on behind the scenes when it comes to maintaining the temperature threshold of the car. 

But as my car started warming up and began performing poorly, I took it to a mechanic, who then made me realize the importance of intercoolers. 

In this article, we are going to learn about intercoolers in detail. Starting from how it works to the benefits. 

So, without wasting time, let’s dive in.

How Do Intercoolers Work with Superchargers (& Why It’s Required)?

An intercooler cools down the air that is compressed by the supercharger. However, this process takes place before it enters the engine. 

Intercoolers are required in supercharged engines to make sure incoming air is cool enough for peak combustion and horsepower.

In simple words, intercoolers take warm air that enters the engine and makes it cooler through heat exchange.

According to the laws of thermodynamics, the larger the temperature difference between the inlet air through the manifold and the combustion temperature within the cylinder, the more energy is converted through the process of combustion. 

Hence, a colder intake implies a bigger temperature difference. So, more power. 

When it comes to a supercharger, the inlet air is made too warm. Using the principles of thermodynamics, in case a fluid is increased in pressure, the fluid temperature also increases. 

Thus, the boost pressure of the turbocharger increases the temperature and pressure of inlet air. In case this isn’t cooled, it will lead to poor engine performance. 

Sure, your supercharger can run without an intercooler but it is recommended to use one for optimum longevity and HP. 

The whole process of cooling is like below:

  1. Air is sucked into the supercharger.
  2. The supercharger then compresses the inlet air into a high-pressure ball and sends it to the intercooler.
  3. An intercooler will cool down the air to an ambient temperature. However, the air might not always be ambient, it might sometimes be hotter. So, the intercooler tries to cool the air as much as possible.
  4. Cooled air is then pushed into the combustion chamber.

Superchargers, as well as turbochargers, work similarly. In the end, the air is compressed and it gets really hot. So, it has to be cooled down.

It is a common misconception that air from superchargers is lower than that of turbochargers. Thus, superchargers do not require intercoolers. However, that is incorrect. 

An Eaton/Magnusson Mp62 supercharger adds on 180 Fahrenheit ambient on a 10psi setup. Thus, the temperature of the outlet is about 250 Fahrenheit on a regular day. 

Nevertheless, the ability has a boost down in rev range where a turbocharger is not an acceptable trade-off.

intercooler-and-supercharger

Intercooler cools down air that’s coming from supercharger. This is important because hot air is not suitable for combustion.

Why Some Superchargers Installation Doesn’t Have an Intercooler?

Some superchargers do not have installed intercoolers as they are more compact than a turbo. This makes it harder to install an intercooler in a supercharger setup. 

Actually, an intercooler installation is not compulsory, either for turbochargers or superchargers. Forced induction systems can run without cooling the air charge. However, when you do so, it can reduce the efficacy of the system. 

Forced induction, irrespective of whether belt-driven works by pushing more air into its inlet point. More air leads to more oxygen. So, with additional fuel, the engine will run with more power. 

It is always recommended to use an intercooler. Once the air is compressed by the supercharger, it can become too hot. Hot air doesn’t hold enough oxygen. 

So, the engine efficiency suffers. The heated inlet air will also cause the temperature of the combustion chamber to increase. 

Hence, a large amount of NOX is formed. It will increase tailpipe emission. Also, it can cause the valves to be damaged permanently.

Installing Supercharger without Intercooler: What Happens?

If an intercooler is not installed in the supercharger, the air coming from the turbo is high in temperature. This, in turn, reduces the machine’s performance. 

Intercoolers are needed to be installed in a turbocharged engine as they can cool down the compressed air that comes from the turbo significantly. It can also help in reducing fuel consumption, improve efficiency, and increase engine power. 

With an intercooler installed in the supercharger, the temperature of compressed air can be reduced from 130 degrees centigrade to 60 degrees centigrade.

It has been able to do this as it has several openings that enable hot air to dissipate heat into the environment. 

Turbocharged engines can produce a large amount of heat as it compresses the air to get the most out of it.

Which muffler is your car right now?

A turbocharger compresses air and this can get very hot and less dense with a lower content of oxygen. This is when the intercooler proves to be useful. 

By installing an intercooler, the compressed air from the turbocharger is cooled down prior to being injected into the engine.

The low temperature of the air enables more oxygen to be dissolved in the charge.

It improves combustion and can reduce heat in every power stroke while helping you save money on gas for every mile you drive. 

An intercooler for the supercharged or turbocharged engine is designed to protect its parts from excessive heat. Thus, it can prevent premature detonation at the time of combustion.

 

Benefits Of Intercooler

  1. Intercooler Keeps the Intake Cooler. It means more horsepower as cooler air is denser and has optimum oxygen for big combustion.
  2. Acts as a Passive Wastegate. So, it can flatten the boost curve at a higher RPM and dial in greater boost at lower RPM ranges for better gains. 
  3. Intercooler Keeps Ignition Time Consistent. It makes sure that the air intake doesn’t become too hot and detonates prematurely. So, it is effective in reducing wear and tear damages.
  4. The Intercooler can Improve Boost Level Safety. Intercooler can keep the intake air cool, letting the turbo work much harder for more boost and power. 

Remember, an intercooler is required for a turbocharged or supercharged vehicle. It also offers several benefits.

Without an intercooler, you can safely do 5psi as the intake air temperature becomes too high. Above 5psi, the air is going to be too hot and can cause internal engine damage.

Where Is the Intercooler Installed on a Supercharger Setup?

The intercooler is installed between the engine and the turbocharger or supercharger.

Superchargers work by compressing air to increase density prior to it reaching the engine’s cylinder.

However, by squeezing a greater amount of air into each cylinder, the engine can proportionally burn more fuel and create more power with every explosion.

The compressing process can generate a great amount of heat. This, in turn, can increase the temperature of the air that enters the engine.

But as the air gets hotter, it tends to become less dense. Thus, it reduces the amount of oxygen that is available in every cylinder and impacts the performance.

Since the intercooler works to counteract this process, it has to be placed between the supercharger and the engine. It provides the engine with more oxygen and improves combustion.

By regulating the air temperature, it can also increase the engine’s reliability by ensuring the fuel to air ratio at every cylinder level.

Best Intercooler for Supercharger: Air-to-Air vs. Water-to-Air

There is no definitive or simple outcome of this debate, except for saying that the decision should depend on the application and why it is going to be used. 

Nevertheless, air-to-air or air-to-water intercoolers have distinct pros and cons. Thus, let’s take a look at each of them.

 

Air-to-Air Intercoolers

Like the term suggests, an air-to-air intercooler uses the cooling effect of the ambient that flows through the core of the unit for carrying away heat.

In the same way as the radiators use airflow through the radiator core for shedding heat from a coolant of a hot engine. It is the best place at the front of the car.

 

Pros of an Air-to-Air Intercooler

  1. Easy to Install. It can be installed in almost every vehicle if the airflow at the installation site is strong enough for flowing through the whole depth of the intercooler core.
  2. Highly Affordable. There are several suppliers of off-the-shelf air-to-air intercoolers, which carry a wide array of intercoolers that have been particularly designed for street use. As the flow characteristics and volume of the unit and extra ducting play a significant role in the efficiency of the coolers, buying a ready-made intercooler for a particular application takes the guesswork out of the equation.
  3. Greatly Reliable. In case an intercooler is constructed and insulated properly against excessive vibration. These units are trouble-free and need to outlast the vehicle. Nevertheless, the core of these intercoolers has to be debugged regularly for maintaining an effective airflow.

 

Cons of an Air-to-Air Intercooler

  1. Poor Efficiency. One of the primary disadvantages of the intercoolers is that their efficiency depends on the road speed and ambient temperature of the vehicle, in case the airflow through the core of the intercooler isn’t supported by a fan. Even though it is not much of a problem in colder climates, it can be an issue in high temperatures.
  2. Air-to-Water Intercoolers. In an air-to-water intercooler, a liquid, such as water or antifreeze is circulated through a set of passages in the actual intercooler, while the intake air passes through another set of passages. Thus, heat is exchanged at the metal interface between the intake air in the intercooler and the coolant. This intercooler can be mounted anywhere on the engine bay. They are a tad smaller than their air-to-air counterparts.

Pros of an Air-to-Water Intercooler

  1. Great Efficiency. The efficiency of an air-to-water intercooler doesn’t depend on the speed of the vehicle. So, the airflow is as much as the previous intercooler.  However, this is only up to a point. In case the application is used for drag racing, the race will get over even before the coolant gets to absorb the required amounts of heat from the engine’s intake air. However, with continuous use for a long period, heat soaking can be a real problem.

 

Cons of an Air-to-Water Intercooler

  1. Complexity These intercoolers depend on the effective circulation of the liquid coolant. This, in turn, needs a supply of liquid coolant, hoses, circulating pump, and heat exchangers for removing heat from the coolant. However, the problem with this is the elements in the system need to be matched with each other if the system has to work efficiently.
  2. Leaks Can Lead to Engine Failure. Even though coolant leaks out of the air-to-water intercooler can be repaired easily, small coolants into intake air passages can lead to misfired and other combustion problems. So, when it comes to choosing one, there is no single set of rules. Hence, all probable variables and their effects have to be taken into account when you diagnose boost pressure or general performance-related problems that are fitted with intercoolers.

Conclusion

A properly placed and well-designed intercooler can boost engine power on a forced-induction engine; it is also true that effective cooling of the intake is just science. So, a small miscalculation or mistake can have a negative impact on the air intake system.

Ifandi S.

Ifandi S.

Passionate about everything mechanical. Ifandi has been involved with motorcycles and cars since the old days - in his family's auto parts shop. Want to keep in touch? Scream "STRAIGHT PIPEEEEE" at the top of your lungs and Ifandi will show up.

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