Intercoolers & Charge Air

Does your engine lose power after a few hard accelerations in a row, or does your turbo or supercharged engine need to keep performance stable in a tuning project? This category brings together parts for cooling the charge air: intercoolers, complete kits, cores, charge pipes, accessories and heat exchangers for water-cooled systems – for street cars and trackday builds alike.

What do an intercooler and charge pipes do?

The turbocharger or supercharger heats the air as it compresses it. Hot air is less dense, and high intake temperatures can cause the engine management to pull ignition timing to protect the engine. An intercooler cools the charge air before it reaches the intake, so performance typically stays more consistent under repeated load. The piping also affects the result: charge pipes with smooth bends and fewer joints can reduce pressure drop and the risk of a hose blowing off at high boost. In a water-cooled system, the coolant releases the heat in a heat exchanger at the front of the car.

How to choose an intercooler

Size alone does not determine performance. Consider several factors together:

• Cooling capacity: the core design, thickness and frontal area determine how much heat can be removed.
• Pressure drop: a dense core can cool well but may require more boost for the same airflow.
• Space: top-mount or front-mount, and whether there is room for the cooler, bumper and piping.
• Power target: a core for mild tuning is not necessarily sized for a bigger turbo upgrade.

An intercooler kit typically includes the cooler, piping and brackets for a specific model, e.g. Subaru WRX, Mitsubishi EVO X, Nissan GT-R (R35) or Porsche Carrera (991.2). If you build your own, a separate intercooler core can be combined with your own end tanks and piping. Brands include Mishimoto, CSF, Wagner Tuning, Wehrli and aFe. Check fitment against model year and engine variant, and regularly inspect clamps, hoses and the core fins for oil, dirt and leaks. Whether the modification can be approved at inspection depends on the product and the car and must be checked for the specific part number.

Frequently asked questions

What is the difference between an air-cooled intercooler and a water-cooled system?

An air-to-air intercooler is cooled by the airflow passing through the core while driving. In a water-cooled system, the charge air transfers heat to coolant, which is then cooled in a separate heat exchanger. Which system your car has depends on the model, and the parts typically cannot be swapped directly.

Does a bigger intercooler always give more power?

No. A bigger core can lower intake temperature, but can also cause more pressure drop and longer piping. The gain depends on boost pressure, power target and how hot the air gets with the stock cooler.

Does the engine management need tuning after an intercooler swap?

It depends on the project. With a direct swap to a model-specific intercooler, it is not always necessary. If you also change piping or boost pressure, you should log boost and intake temperature and possibly have the software adjusted.

How do you detect a leaking charge air connection?

Typical signs are a hissing sound under acceleration, lower boost than normal, oil at the joints or boost-related fault codes. Check clamps and hoses, and look for cracks or a hose that has slipped off.