Process West Top Mount Intercooler – Subaru GD WRX/STI (01–02) – Black

The Process West Top Mount Intercooler Kit for the 2001–2005 Subaru WRX and STI (GD chassis) is engineered to be the most effective top mount intercooler upgrade available. Developed through extensive testing and refinement, this kit delivers superior performance, cooling efficiency, and design integration compared to all other aftermarket options.

While other brands offer oversized cores with stock under-bonnet shrouds, Process West addresses this critical flaw by including a custom-designed bonnet splitter/shroud to direct full ambient airflow across the entire core surface. Without proper airflow coverage, larger intercoolers are severely limited in effectiveness — something Process West has completely resolved.

With a massive 175mm x 490mm x 90mm bar-and-plate core, this intercooler is large enough to handle serious power while remaining thin enough (90mm) to promote efficient heat exchange, even under low airflow conditions such as circuit driving or heat soak scenarios. Thicker 114mm cores used by competitors often restrict airflow and result in higher charge temps — an issue Process West has purposely avoided.

Optimised Y-Pipe Design:
Process West also addresses another common issue: poor airflow distribution from conventional Y-pipes. The included silicone Y-pipe is specifically engineered to deliver even airflow to both sides of the core, improving response and consistency.

Dyno-Tested Performance:
Independent dyno testing on a lightly modified 2005 WRX showed an increase of 8kW at the wheels compared to the stock intercooler — with lower charge temps (51°C vs 66°C). During repeated runs, the stock intercooler’s outlet temps climbed to 84°C, while the Process West unit stayed well within safe ranges.

Street-Tested Cooling:
Road testing in real-world conditions showed a peak intercooler outlet temp of only 43°C with the Process West unit, compared to 72°C on the factory setup — proving its efficiency under extended load.

Key Features:
– Largest and most efficient TMIC available for GD WRX/STI
– Bar-and-plate core (175mm x 490mm x 90mm)
– Custom bonnet splitter/shroud for complete airflow coverage
– High-efficiency silicone Y-pipe for balanced charge flow
– No cutting or trimming required
– Proven dyno and street-tested gains

Fitment:
Subaru WRX GD – 2001–2005
Subaru WRX STI GD – 2001–2005

Collection:
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