Mishimoto Subaru WRX/STi Front-Mount Intercooler Kit, Part 4: Intercooler Pipe Fabrication/Development

Mishimoto Subaru WRX/STi Front-Mount Intercooler Kit, Part 4: Intercooler Pipe Fabrication/Development

Interested in purchasing our Subaru WRX or STi intercooler kit? Check out more details on our product pages linked below!

Mishimoto Subaru WRX/STi Front-Mount Intercooler, 2001-2007

Mishimoto Subaru WRX Front-Mount Intercooler, 2008-2014

Mishimoto Subaru STi Front-Mount Intercooler, 2008-2014

Time to weld up some pipes! This would be the more time-consuming portion of this project, as most of these vehicles would require a specific pipe kit. We would not be able to utilize one set of pipes across the model board, as we did with the intercooler. Going in order, we started with our Bugeye. One of our test vehicles featured a reasonably stock engine bay, as shown below.

Stock Bugeye engine bay
Stock Bugeye engine bay

After ripping the stock cooler off of both our wagon and sedan test vehicles, we began to fabricate piping. Check out a few shots of what our engineers came up with for routing!

Mishimoto fabricated intercooler pipes on Bugeye
Mishimoto fabricated intercooler pipes on Bugeye

Mishimoto fabricated intercooler pipes on Bugeye
Mishimoto fabricated intercooler pipes on Bugeye

Mishimoto fabricated intercooler pipes on Bugeye
Mishimoto fabricated intercooler pipes on Bugeye

These pipes fit very nicely and required little vehicle modification. This kit does require that the overflow bottle be removed. We are including our own overflow bottle which is relocated slightly. Additionally we will be adding the bypass flange to the cold-side pipe. These pipes will be all aluminum and we will be offering them in a polished finish. Mishimoto silicone couplers will also be included to mate the pipes to each other and to the cooler. Check out the shot below showing our replacement aluminum reservoir in place as well as our BPV port.

Mishimoto coolant reservoir mounted on Bugeye
Mishimoto coolant reservoir mounted on Bugeye

Next it was time for the Hawkeye. This particular model utilizes a drive-by wire throttle body which required some adjustments to the upper piping. The lower piping is very similar to that of the previous body.

Hawkeye drive-by wire throttle body
Hawkeye drive-by wire throttle body

Hawkeye piping mock-up
Hawkeye piping mock-up

As you can see we've made a few changes with the upper hot-side pipe. The pipe has been shortened, and we are using a longer coupler which routes around the throttle body sensors. This provides the clearance we need to allow for smooth airflow.

With the GD chassis settled, it was time to move on to the GR models. First, we brought in a WRX test vehicle to begin fabrication. Due to the significant engine bay differences, we would not be using any of the pipes from the previous kit, so this one was going to be fabricated from the ground up.

The 2008-2014 WRX uses an interesting intercooler connection point on the compressor outlet. This model uses a two-bolt flange that mates directly to the intercooler end tank on the stock vehicle. The compressor housing is threaded and two bolts go through the intercooler flange and into the turbo. We would need to develop an adapter to convert from the flange to our projected pipe size for the kit. We used the measurements from the stock intercooler to design this flange in Solidworks. We then used our 3D printer to produce a working prototype. This was then epoxied to our intercooler pipe in order to fabricate the rest of the piping. Check out the adapter!

GD WRX turbo compressor adapter
GD WRX turbo compressor adapter

Once we had this component we could begin fabricating the rest of the piping for the WRX. Check out the process below!

GD WRX intercooler pipe fabrication
GR WRX intercooler pipe fabrication

GD WRX intercooler pipe fabrication
GR WRX intercooler pipe fabrication

GD WRX intercooler pipe fabrication
GR WRX intercooler pipe fabrication

GD WRX intercooler pipe fabrication
GR WRX intercooler pipe fabrication

Now that we had the pipes routed, we could fully installed the cooler and ensure everything was mating up perfectly.

GD WRX intercooler kit mock-up
GR WRX intercooler kit mock-up

GD WRX intercooler kit mock-up
GR WRX intercooler kit mock-up

Another pipe kit in the books! Check back next time for the development of our final pipe kit for the 2008-2014 STI!

Thanks for following!

Interested in purchasing our Subaru WRX or STi intercooler kit? Check out more details on our product pages linked below!

Mishimoto Subaru WRX/STi Front-Mount Intercooler, 2001-2007

Mishimoto Subaru WRX Front-Mount Intercooler, 2008-2014

Mishimoto Subaru STi Front-Mount Intercooler, 2008-2014