Process West Silver Top Mount Intercooler Subaru STI 2008-2021 | PWTMIC06

Product Fitment: 2008–2021 Subaru STI (GRB 2008–2014 & VA 2015–2021)

Overview

The Process West Silver Top Mount Intercooler (PWTMIC06) is a high-capacity upgrade engineered specifically for the 2008–2014 GRB STI and 2015–2021 VA STI. Designed for performance Subaru builds that demand greater cooling consistency under sustained load, this kit replaces the restrictive factory intercooler with Process West's largest available Subaru top-mount core. Whether you're running a mild tune or a high-output STI build, the PWTMIC06 delivers improved charge-air cooling and more predictable power delivery.

Key Features & Benefits

• Massive 530 × 193 × 90mm Bar-and-Plate Core — Process West's largest Subaru top-mount core provides a significant increase in cooling surface area over the factory intercooler, helping reduce intake air temperatures and combat heat soak during hard driving.
• Improved Charge-Air Cooling — Greater core volume and surface area translate to lower charge temperatures, supporting more consistent power output and improved throttle response run after run.
• Engineered Silicone Y-Pipe — The included Process West silicone Y-pipe distributes compressed air evenly across the full width of the intercooler core, preventing hot spots and maximizing the effectiveness of the upgraded unit.
• Balanced Airflow Distribution — Even charge-air distribution across the core ensures the entire cooling surface is utilized, rather than concentrating airflow in one section as OEM-style setups often do.
• Heat Soak Resistance — The bar-and-plate construction retains less heat than tube-and-fin designs, making it better suited for track use, repeated pulls, and tuned applications.
• Complete Bolt-On Kit — Comes with all required installation hardware and fittings for a straightforward fitment on both GRB and VA STI platforms.

What's Included

• Process West PWTMIC06 silver top mount intercooler
• Process West silicone Y-pipe
• Required installation hardware and fittings

Specifications

Fitment & Compatibility

This intercooler kit is designed to fit the following Subaru STI applications:

• 2008–2014 Subaru Impreza WRX STI (GRB chassis)
• 2015–2021 Subaru WRX STI (VA chassis)

Fitment covers both the GRB and VA STI generations. If you are unsure which chassis code applies to your vehicle, confirm your model year and body style before ordering. This intercooler is purpose-built for the STI top-mount intercooler location and is not compatible with WRX front-mount intercooler setups.

Installation

The Process West PWTMIC06 is designed as a direct-fit top mount intercooler upgrade for the 2008–2021 Subaru STI. The kit includes all necessary hardware and the silicone Y-pipe, making installation straightforward for an experienced DIY installer or performance shop. Basic hand tools are required. A professional installation is recommended for those unfamiliar with intercooler replacement or Subaru EJ/FA-series forced induction systems. A retune is strongly advised after installation to take full advantage of the improved cooling capacity.