Subaru STi Intercooler 2008-2014

Interested in purchasing our STI intercooler? Check out our product page for more information!

Mishmoto Subaru WRX STi Performance Top-Mount Intercooler Kit

Testing day! After a long ride through development and design, it was finally time to see the fruits of our labor. Before strapping the STI to the dynamometer, we needed to prepare the coolers for testing. This included drilling and tapping the coolers for our temperature and pressure sensors at both the inlet tank and outlet tank.

Check out a few preparation shots of our stock cooler!

Stock intercooler testing preparation

Stock intercooler tapped for sensors

Stock intercooler with sensor installed

Next up is the Mishimoto cooler. For testing we used our powder-coated cooler rather than the raw aluminum unit. (The finish has little to no effect on performance.) This version of the cooler is identical to what we have planned for mass production, assuming our testing is successful.

Mishimoto intercooler tapped

Mishimoto intercooler with

Interested in purchasing our STI intercooler? Check out our product page for more information!

Mishmoto Subaru WRX STi Performance Top-Mount Intercooler Kit

The wait is over! Time to reveal the full details of our prototype top-mount intercooler (TMIC). This unit is unpainted, and one of the more obvious features is its massive size! First, a few overview images of this cooler.

Mishimoto raw aluminum TMIC prototype

Mishimoto raw aluminum TMIC prototype

Mishimoto raw aluminum TMIC prototype

As you can see we designed two fully casted end tanks for this cooler. Both the BPV flange and Y-pipe flanges are CNC-machined. The thickness and construction of our casting will provide the durability needed to run much higher pressures than your STI will ever see. Each tank is then TIG-welded to our core. As with other projects, we are using a bar-and-plate core for improved heat transfer and resistance to heat soak. Let's take a closer look at the core itself.

Mishimoto TMIC prototype, external core

Interested in purchasing our STI intercooler? Check out our product page for more information!

Mishmoto Subaru WRX STi Performance Top-Mount Intercooler Kit

Did you think we would just develop a top-mount intercooler (TMIC) for the GD WRX and leave out the STI? No way! At around the same time we began development on the WRX, we picked up a new shop vehicle, a 2010 STI. When a new vehicle makes its way into shop service, we need to be sure it accelerates and handles properly. The STI passed our checkup. We then set out to determine what products we wanted to develop first. We already had a few items on the market, including a performance aluminum radiator and a silicone radiator hose kit. Our first target had been a direct-fit oil cooler that proved to be extremely successful, providing a 20°F drop in oil temperatures during our testing. Next we created a plug-n-play fan shroud with dual 12" electric fans. The key component of this shroud was the use of stock-style fan connectors and a very