Invidia High-Flow Catted Downpipe - 2015-2021 Subaru WRX (Manual Transmission)

Unlock Stage 2 performance from your WRX with the Invidia high-flow catted downpipe. Engineered specifically for the 2015-2021 Subaru WRX with manual transmission, this premium downpipe features 3-inch mandrel-bent stainless steel construction with a high-flow catalytic converter that significantly reduces backpressure while maintaining emissions compliance in most jurisdictions.

Key Features:

• 3-inch mandrel-bent stainless steel construction for maximum flow
• High-flow catalytic converter for emissions compliance
• Designed specifically for manual transmission WRX (2015-2021)
• Direct bolt-on fitment - no modifications required
• TIG-welded construction for strength and durability
• Includes all necessary gaskets and hardware
• Essential for Stage 2 tuning
• Invidia quality engineering and manufacturing

Performance Benefits:

• Significant Power Gains: 20-30+ HP when combined with intake and ECU tuning
• Reduced Backpressure: 3-inch piping eliminates factory restriction
• Improved Turbo Spool: Reduced backpressure allows turbo to spool faster
• Enhanced Exhaust Sound: Deeper, more aggressive turbo and exhaust note
• Stage 2 Ready: Essential component for Stage 2 ECU tuning
• Emissions Friendly: High-flow cat maintains emissions compliance in most areas

Specifications:

• Brand: Invidia
• Part Number: HS15SWMDOC
• Piping Diameter: 3 inches
• Material: Mandrel-bent stainless steel
• Construction: TIG-welded
• Catalytic Converter: High-flow (emissions compliant)
• Transmission: Manual only
• Installation: Direct bolt-on
• Weight: 21.5 lbs
• Barcode: HS15SWMDOC

Fitment Information:

• Compatible Vehicles:
• 2015-2021 Subaru WRX (FA20DIT engine, manual transmission only)
• Note: This downpipe is designed ONLY for manual transmission WRX. NOT compatible with CVT automatic transmission models.

What's Included:

• Invidia high-flow catted downpipe
• Exhaust gaskets
• Stainless steel mounting hardware
• Installation instructions

Installation Notes:

• Professional installation strongly recommended
• Installation time: approximately 3-4 hours
• Vehicle must be lifted or on jack stands for installation
• ECU tuning REQUIRED after installation - will trigger check engine light without tune
• Torque all fasteners to manufacturer specifications
• Allow exhaust to cool completely before installation

IMPORTANT - ECU Tuning Required:

WARNING: Installing this downpipe will trigger a check engine light (CEL) without proper ECU tuning. You MUST have an ECU tuner such as COBB Accessport or work with a professional tuner to flash Stage 2 maps after installation. Do not install this downpipe without tuning support.

Manual Transmission Only:

IMPORTANT: This downpipe is designed specifically for manual transmission WRX models. The manual and CVT automatic transmission WRX have different exhaust routing and are NOT interchangeable. Verify your WRX has a manual transmission before ordering.

Why High-Flow Catted?

The Invidia catted downpipe features a high-flow catalytic converter that significantly reduces backpressure compared to the factory downpipe while maintaining emissions compliance in most jurisdictions. This makes it more emissions-friendly than cat-delete downpipes while still delivering excellent performance gains. The high-flow cat also helps reduce the likelihood of check engine lights related to emissions monitoring.

Stage 2 Performance:

The downpipe is the key component for achieving Stage 2 performance on the FA20DIT WRX. When combined with an intake and Stage 2 ECU tuning, expect power gains of 20-30+ HP and 30-40+ lb-ft torque over stock. The reduced backpressure also improves turbo spool, throttle response, and overall drivability.

Why Mandrel-Bent?

Invidia uses mandrel bending for all piping, which maintains consistent diameter throughout each bend. This eliminates the rippling and crimping that occurs with crush bending, ensuring smooth, unrestricted exhaust flow. The result is maximum power gains and improved turbo response.

Why Invidia?

Invidia is a globally recognized leader in performance exhaust systems, known for exceptional quality, precise fitment, and proven performance. Every Invidia downpipe is designed vehicle-specific and manufactured to exacting standards using premium materials. Their catted downpipes are trusted by thousands of WRX owners worldwide.

Emissions & Legality:

The Invidia catted downpipe includes a high-flow catalytic converter, making it more emissions-friendly than cat-delete alternatives. However, emissions laws vary by jurisdiction. Always check your local laws and regulations before purchasing. This downpipe may not be legal for street use in all areas.

Sound Level:

Expect a noticeable increase in exhaust volume and a deeper, more aggressive tone. The turbo will be more audible, with enhanced turbo spool and wastegate sounds. Cold starts will be louder. The sound is aggressive but refined - not excessively loud for daily driving.

Perfect For: WRX owners looking to achieve Stage 2 performance, improve turbo spool, enhance exhaust sound, or anyone building a modified FA20DIT engine.

Pro Tip: Install the downpipe along with an intake and have your ECU tuned for Stage 2 all at once. This ensures optimal performance and prevents running the car with mismatched modifications.

Essential Upgrade: The catted downpipe is considered mandatory for Stage 2 WRX builds and delivers the most significant performance gains of any single bolt-on modification.

Transform your Subaru WRX with Invidia's high-flow catted downpipe - the foundation for Stage 2 performance.