Intercooler vs Radiator: What’s the Difference?

At first glance, intercoolers and radiators might seem to serve the same purpose: cooling. However, both of these systems serve a unique function, and are not interchangeable. While both are integral to maintaining optimal engine temperatures, they cater to different aspects of the engine's cooling needs. The radiator's primary function is to reduce the temperature of the engine coolant, while the intercooler's main job is to cool the compressed air from the turbocharger before it enters the engine. We'll explore the fundamental differences of radiators vs intercoolers, highlighting the unique contributions each makes to a vehicle's performance.

Related: If you would like to learn more about radiators vs intercoolers, check out our guides on types of intercoolers and how to choose the right radiator.

What Is An Intercooler?

An intercooler is a heat exchanger that cools the air compressed by a turbocharger or supercharger before it enters the engine's combustion chamber. Intercoolers typically come in either air-to-air or air-to-water designs, depending on how the exhaust gasses are cooled. In a turbocharged vehicle, exhaust gasses travel from the exhaust manifold to the turbocharger. The force from the exhaust is rerouted to add pressure to the air intake system. The very hot exhaust gasses need to be cooled by an intercooler to make them useful for forced engine induction. By cooling this compressed air, the intercooler increases air density. This allows for more oxygen to enter the engine, leading to better fuel combustion and increased power output.

What Is A Radiator?

A radiator is a part of the vehicle's cooling system that diffuses heat from the engine coolant and recirculates the fluid. A vehicle's engine coolant circulates through the engine, absorbing the heat produced during combustion. When it reaches the radiator, the coolant flows into small rows of tubes. The car's movement forces air through the rows that run between the tubes, reducing the temperature of the coolant. Exposing the coolant to a large volume of cool air dissipates the heat through the vehicle's grille. The coolant is then returned to the engine where the cycle restarts.

Differences Between Radiators vs Intercoolers

Intercooler: An intercooler's primary function is to cool the hot exhaust gasses from a vehicle's turbocharger or supercharger. Cooler air is denser and contains more oxygen molecules per unit volume. This allows for a better air-fuel mixture and a more efficient combustion process. Intercoolers disperse the heat from exhaust gasses either through fins that receive airflow in an air-to-air system or through water in an air-to-water system. The Intercooler then recirculates the cooled gasses back to the engine, adding pressure to the air intake system.

Radiator: A Radiator's main role is to maintain the engine's optimal operating temperature. The radiator prevents the engine from overheating by dissipating the heat from the engine coolant. As engine coolant heats up from the combustion process, it travels through the lower radiator hose, where it is forced through a large array of tubes. These tubes increase the contact surface area of the hot coolant with cool air from the vehicle's movement and the radiator fan, cooling the fluid. The cooled fluid then recirculates through the upper radiator hose back to the engine for reuse.

Where Are Intercoolers and Radiators Located?

Intercooler: The Intercooler is typically located near the front of the vehicle, often behind the front bumper or grille, to ensure maximum airflow. Some vehicles may also have a top-mounted intercooler, usually situated on the engine or near the intake manifold. Air-to-water intercoolers are more flexible in their placement and can be found in various places throughout the engine bay depending on the vehicle.

Radiator: A vehicle's radiator is almost always located at the front of the vehicle, directly behind the front grille. This ensures it receives a constant flow of fresh air when the vehicle is in motion.

Types of Radiators and Intercoolers

Intercooler

Air-to-Air Intercooler:

Air-to-air intercoolers are the most common type of intercooler. They are typically mounted in the front of the engine bay, allowing easy access to cool outside air. This makes them cheaper, lighter, and simpler in design compared to air-to-water intercoolers.

However, their front-mounted position requires longer intake tubing to reach the engine. This can lead to greater temperature fluctuations. Air-to-air intercoolers also rely solely on ram air while driving, so they are prone to heat soak at idle.

These intercoolers feature either a tube-and-fin or bar-and-plate core design. The tube-and-fin type uses numerous small tubes lined up in parallel. Fins surround the tubes to increase surface area and cooling efficiency. Bar-and-plate cores consist of alternating layers of flat bars and finned plates stacked together. Both core types aim to maximize heat transfer while minimizing pressure drop.

Air-to-Water Intercooler:

Air-to-water intercoolers, also known as air-to-liquid intercoolers, use water or coolant to transfer heat away from the intake air as it passes through the system. The intercooler extracts heat from the compressed air coming from the turbo or supercharger. This cooled air then flows into the engine, while the warmed water cycles through a separate cooling system, typically flowing through a dedicated radiator.

While more complex, air-to-water intercoolers offer superior cooling performance compared to air-to-air designs. However, they are heavier and more expensive because they require coolant lines, a water pump, radiator, and associated components. Unlike air-to-air intercoolers mounted up front, air-to-water systems can be positioned in different areas of the engine bay, provided there is sufficient airflow across the radiator or an electric cooling fan is used.

Radiator

Downflow vs Crossflow Radiator:

The direction of the fins indicates whether a radiator is a crossflow or downflow type. The fins in a crossflow radiator are horizontal. The fins in a downflow radiator are vertical.

The path the coolant takes through the radiator also differs. Coolant enters at the top of a downflow radiator, flowing down through the vertical fins before exiting out the bottom. With a crossflow, coolant flows horizontally, entering on one side and traveling across the fins to the outlet on the opposite side. Crossflow radiators are commonly used in modern vehicles due to their efficient cooling capabilities and compact size. Downflow radiators were more prevalent in older cars.

Two vs Three Row Radiator:

Radiators use rows of tubes and fins to efficiently transfer heat from coolant to air. Adding more rows increases the total surface area for heat transfer, which improves cooling capacity. However, the number of rows needs to be balanced against tube width.

Sometimes a radiator with fewer rows can outperform a radiator with more rows because the former has larger diameter tubes. More rows can also make the radiator thicker, which restricts airflow and offsets some of the gains. Using aluminum instead of traditional copper-brass allows manufacturers to add rows and width without significant weight or thickness penalties.

How Important are Intercoolers vs Radiators for Vehicle Performance?

Intercooler: Intercoolers are essential for turbocharged and supercharged engines. A well-functioning intercooler can significantly improve horsepower and torque by ensuring that the engine receives a consistent supply of cool, dense air. Vehicles without a supercharger or turbocharger do not need an intercooler.

Radiator: Radiators are vital for all internal combustion engines, irrespective of whether they are naturally aspirated, turbocharged, or supercharged. A malfunctioning radiator can lead to engine overheating, resulting in decreased performance, engine knock, or even catastrophic engine failure.

Find the Best Intercooler or Radiator for Your Vehicle

While there are several key differences when comparing radiators vs intercoolers, they both play crucial roles in ensuring the optimal performance and longevity of your vehicle's engine. Intercoolers focus on cooling the hot air from turbochargers or superchargers, enhancing engine efficiency and power. Radiators maintain the engine's temperature by lowering the temperature of the engine coolant.

It's important to keep these components in top condition, as they are key to the health of your vehicle's engine. If your radiator or intercooler needs a replacement, we offer quality aftermarket Mustang radiator and intercooler options that will help keep your engine cool and functional. Shop our wide selection of parts below.

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