2Pc Manifold Header+Up-pipe/Exhaust For 02-07 Subaru Impreza Wrx/sti Ej25 2.5L

What is 2Pc Manifold Header+Up-pipe/Exhaust For 02-07 Subaru Impreza Wrx/sti Ej25 2.5L?

This performance exhaust system is engineered for 2002–2007 Subaru Impreza WRX and STI models equipped with the 2.5L EJ25 turbocharged engine. It replaces the factory exhaust manifold and up-pipe with a high-flow 4-1 header design that enhances exhaust scavenging, reduces backpressure, and supports measurable gains in horsepower and torque—reported at 10 to 15 hp. Constructed from high-quality stainless steel and TIG welded for strength, this two-piece header and up-pipe assembly ensures long-term durability under high-heat and turbocharged conditions. It includes a metal gasket and necessary hardware for installation, though no instructions are provided.

Key features

• Stainless Steel Build — High-quality stainless steel resists corrosion and handles high exhaust temperatures.
• TIG Welded Construction — Precision welding ensures structural integrity and leak-free performance.
• 4-1 Racing Header Design — Optimized for improved exhaust flow and scavenging efficiency.
• CNC-Machined Flange — Ensures precise fitment with the cylinder head and turbocharger.
• O2 Sensor Bung — Includes proper bung for oxygen sensor installation.
• Includes Metal Gasket — High-temp gasket included for reliable sealing.
• Direct Fit for EJ25 — Designed specifically for 2002–2007 WRX/STI 2.5L turbo models, excluding certain years.

Who is 2Pc Manifold Header+Up-pipe/Exhaust For 02-07 Subaru Impreza Wrx/sti Ej25 2.5L for?

This header system is ideal for Subaru enthusiasts and performance tuners upgrading their EJ25-powered WRX or STI. It suits DIY mechanics with welding and exhaust experience or those using professional installers. It’s a smart choice for builds focused on increasing turbo response, exhaust efficiency, and overall engine output. Not recommended for stock daily drivers without supporting modifications.

How does 2Pc Manifold Header+Up-pipe/Exhaust For 02-07 Subaru Impreza Wrx/sti Ej25 2.5L compare?

Compared to stock manifolds, this 4-1 stainless steel header offers superior flow, heat resistance, and power gains. It outperforms mild steel headers in durability and corrosion resistance. While long-tube headers on other platforms may offer more peak power, this design balances gains with fitment in the WRX/STI engine bay. It’s a cost-effective upgrade over full turbo-back systems for those targeting mid-range torque and turbo spool improvements.