2004 Subaru WRX - Keeping Under Pressure Cool - Tech Knowledge

Remove the factory top-mount intercooler via the identified bolts on either side of its core, and then loosen the hose clamps securing it onto the throttle body and turbo outlet.

With the stock intercooler removed and compared to the Perrin FMIC, the increase in size is apparent, as well as the design improvements brought by the Perrin's high-capacity, bar-and-plate design.

Next up, remove the OE intake inlet and plumbing: Make sure to remove the entire assembly, including what extends into the engine bay from the fender. This will clear a path for the Perrin intercooler piping.

Before bolting up any of the tubing, make sure to adjust the location of this brake-line coupler, according to your year/model WRX. Ours only had to be moved slightly, to allow passage to the Perrin charge tubing.

With all previous steps completed, installing the intercooler tubing is a bolt-on affair. Start at the turbo outlet, using the S-shaped silicone coupler to join the turbo outlet to its immediate section of tube. Next, install the section of tubing feeding the throttle body. You'll have to manipulate these two sections of tubing and their couplers a little to get them to work well together, hence the "S" shape of the turbo outlet coupler. Marc is planning "something different" with his GReddy blow-off valve down the road, so we just set it to vent to atmosphere for the time being, using an included section of silicone tubing.