Cobb TD05H-20G-8 Turbocharger for WRX STI

Part Details:

The COBB TD05H-20G-8 Turbocharger is a performance upgrade engineered for Subaru WRX and STI applications seeking increased airflow and reliable power gains while maintaining street-friendly drivability. Designed as a bolt-on solution for compatible EJ-platform vehicles, this turbo offers a balanced powerband ideal for enthusiasts targeting strong midrange torque and improved top-end performance.

Built around a proven TD05H turbine architecture and 20G compressor design, the COBB TD05H-20G-8 supports significant horsepower increases when paired with proper fueling upgrades and professional ECU calibration. The 8cm² turbine housing provides responsive spool characteristics while allowing the turbo to carry power efficiently through higher RPM ranges.

Key Features

• Performance 20G compressor wheel for increased airflow capacity
• TD05H turbine design for proven durability and response
• 8cm² turbine housing for balanced spool and top-end power
• Designed for bolt-on compatibility with supported Subaru WRX/STI models
• Optimized for use with COBB tuning solutions

Fitment

Compatible with select Subaru WRX and STI EJ-series turbocharged applications. Fitment should be confirmed based on model year and existing modifications.

Supporting Modifications

Upgrading to a turbocharger of this size requires supporting modifications including fuel system upgrades, intercooling improvements, and professional ECU calibration. Clutch and drivetrain upgrades may be necessary depending on intended power levels.

Frequently Asked Questions

Is tuning required?
Yes. Professional ECU calibration is required to safely operate this turbocharger and achieve proper air-fuel and boost control.

Is this a good daily-driver turbo?
Yes. The TD05H-20G configuration offers a strong balance between spool response and peak power, making it suitable for performance-oriented street builds.

What power levels can this support?
Horsepower capability depends on supporting modifications and fuel type, but this turbo is commonly used in mid-to-high horsepower EJ builds.

Recommended Supporting Forced Induction Components

• Intercooler Kits – help control intake temperatures and reduce heat soak at higher boost levels.
• Boost Controllers – improve boost targeting accuracy and consistency when upgrading turbochargers.
• Wastegates – regulate boost pressure and support stable turbo system operation under load.
• Turbo Inlets – support improved airflow to the turbocharger and reduce intake-side restriction.
• Turbo Bypass Valves – help manage excess boost pressure and maintain smooth drivability during throttle changes.
• Fuel Delivery Upgrades – commonly required to support higher airflow and maintain safe air-fuel ratios.
• EFI Tuning – tuning is required to calibrate boost control, fueling, and ignition after a turbo upgrade.
• Clutch Kits – increased torque often requires upgraded clutch capacity to prevent slip.
• COBB Tuning Performance Products – explore supporting tuning and turbo system components from COBB.
• Subaru WRX Performance Parts – browse supporting upgrades for WRX turbo builds.
• Subaru STI Performance Parts – explore turbo system and supporting components for STI applications.
• Subaru Forester XT Performance Parts – find forced induction upgrades for Forester XT builds.