Cooling

The best cooling upgrades for a turbocharged WRX or STI start with the parts that fight heat soak: a larger top-mount intercooler, smooth-flowing charge pipes, and an aluminum radiator with more core volume than stock. For the 22+ WRX, a quality top-mount intercooler from ETS or AMS paired with upgraded charge pipes is the proven combo for consistent power on hot days. If your car runs hot in traffic or on track, a performance radiator is the next step — always match the radiator to your transmission type, since automatic and manual cars often use different units.

Turbo Subarus make a lot of heat, and heat kills power. The intercooler cools the compressed air from the turbo before it reaches the engine — a bigger, better-flowing core means denser air and more consistent timing pull after pull. Charge pipes replace the restrictive factory plumbing between the turbo, intercooler, and throttle body. The radiator handles engine coolant; aluminum performance radiators cool better and resist the plastic end-tank failures that plague high-mileage stock units.

Top brands here include ETS (Extreme Turbo Systems), AMS Performance, COBB Tuning, Koyo, Torque Solution, and Mishimoto — plus radiators in Performance Radiators. Standouts include the Koyo radiator for 08–21 WRX/STI, the ETS 22+ WRX top-mount intercooler, and the AMS 22+ WRX top-mount intercooler. Learn why it matters in why you should install an intercooler kit.

Does an intercooler upgrade require a tune?

A drop-in intercooler on the stock turbo generally doesn't demand a tune by itself, but pairing it with charge pipes or intake changes the equation — check with your tuner before stacking mods.

Will a performance radiator fit my automatic?

Not always — automatics often need a radiator with transmission cooler fittings. Check the transmission fitment on the product page (our Koyo listing is manual-transmission specific) and confirm your year and model.

How hard is a top-mount intercooler to install?

A moderate DIY job: basic hand tools, an hour or two, and careful handling of the turbo-to-intercooler couplers. Charge pipes add a bit more time since access is tighter.

Do I need an oil cooler too?

For street driving, usually not. If you track the car or live somewhere brutally hot, an oil cooler is cheap insurance against heat-related wear.