Cobb Stg 1+ Drivetrain Pkg (Tall Weighted Knob) - White - 2004-2021 Subaru STI 6MT

The Uppipe: The Restriction Between the Engine and the Turbo

The Cobb Stainless Steel Uppipe for the Subaru replaces the restrictive factory unit between the exhaust manifold and the turbocharger. The factory uppipe contains a flex section that collapses over time and a catalytic converter that restricts exhaust flow before it reaches the turbine wheel. The Cobb uppipe removes both restrictions, improving exhaust gas flow to the turbine and reducing the heat buildup that the factory flex section traps.

Better Flow to the Turbine Wheel

Reducing restriction in the uppipe directly improves how quickly exhaust gas reaches the turbine wheel on the Subaru. The turbine spins on exhaust energy — more energy arriving with less restriction means faster spool and better mid-range boost delivery. The Cobb uppipe also removes the pre-turbo catalyst that traps heat in the exhaust path before the turbocharger.

Bolt-In at Factory Manifold and Turbo Flanges

The Cobb uppipe bolts to the factory exhaust manifold and turbocharger flanges on the Subaru with no modification to the chassis or engine. The factory O2 sensor location is retained for ECU compatibility. An Accessport tune is required after installation.

Key Features

• Platform: Subaru
• Material: 304 Stainless Steel — durable, mandrel-bent throughout
• Bolt-in at factory connection points — no chassis modification required
• Accessport tune required after installation

Fitment Notes

• Platform: Subaru
• Accessport tune required after installation — do not run on stock ECU calibration
• Connects at factory downpipe flange — verify downpipe connection compatibility

Straight From Subispeed

The Cobb uppipe is one of the most underrated upgrades on the Subaru — it directly improves the exhaust gas energy reaching the turbine wheel, which shows up as improved spool speed and better mid-range boost delivery before the downpipe is even touched.

What's Included

• Cobb Stainless Steel Uppipe — Subaru
• All gaskets and hardware

About Cobb Tuning

Cobb Tuning has been developing performance parts and tuning solutions for Subaru vehicles since 1999. Based in Austin, Texas, Cobb built their reputation on the Accessport — the most widely used Subaru ECU tuning device on the market — and expanded that into a full ecosystem of intake, exhaust, drivetrain, and engine bay accessories engineered specifically for the platforms they support. Every Cobb product is developed in-house and validated on their own test vehicles before it reaches customers. Subispeed carries the full Cobb catalog because their engineering standards and platform-specific development process consistently produce parts that work exactly as advertised.