OAO Valved Sport Cat-Back Exhaust System for Porsche 991.1 / 991.2 GT3 / GT3 RS 4.0L Flat-Six

Unleash the Motorsport Soul of the Porsche GT3

Designed specifically for the Porsche 911 GT3 and GT3 RS across the 991.1 and 991.2 generations, the OAO Valved Sport Cat-Back Exhaust System is engineered to enhance the naturally aspirated 4.0L flat-six engine with improved exhaust flow, reduced restriction, and an unmistakable motorsport-inspired sound.

Developed for enthusiasts who demand more from Porsche's legendary high-revving GT platform, the OAO Valved Sport Cat-Back combines precision exhaust engineering with electronically controlled valves, allowing drivers to choose between refined street cruising and an aggressive, race-inspired exhaust character.

Manufactured from premium T304 stainless steel with precision TIG welding, mandrel-bent tubing, and high-flow muffler technology, the system is built to withstand the extreme temperatures and high-RPM demands of the GT3 platform.

Key Features

✓ Designed for Porsche 991.1 / 991.2 GT3 & GT3 RS

✓ 4.0L Naturally Aspirated Flat-Six Engine

✓ Valved Sport Cat-Back Exhaust System

✓ Electronically Controlled Exhaust Valves

✓ Premium T304 Stainless Steel Construction

✓ High-Flow Muffler Design

✓ Precision TIG Welded

✓ Mandrel-Bent Tubing

✓ Optimized Exhaust Gas Flow

✓ Reduced Exhaust Restriction

✓ Lightweight Performance Construction

✓ OEM-Style Direct Bolt-On Installation

Intelligent Valved Exhaust Control

Comfort / Street Mode

With the valves closed, the OAO system delivers a deeper yet controlled exhaust tone, making the GT3 more comfortable for everyday driving and highway cruising.

Ideal for:

• Daily Driving

• Highway Cruising

• Long-Distance Touring

• Residential Areas

• Reduced Exhaust Volume

• Comfortable Street Use

The result is a refined Porsche experience without sacrificing the character of the naturally aspirated flat-six.

Sport / Open Valve Mode

Open the valves and unleash the full motorsport character of the GT3.

Experience:

• Significantly Increased Exhaust Volume

• Sharper Throttle Acoustics

• Richer Flat-Six Sound

• Aggressive Acceleration Note

• Enhanced High-RPM Exhaust Character

• More Pronounced Downshift Sound

• Race-Inspired Driving Emotion

At high RPM, the OAO system allows the naturally aspirated 4.0L engine to deliver the raw, mechanical soundtrack that makes the GT3 so special.

Performance-Oriented Exhaust Design

The OAO Valved Sport Cat-Back is engineered to improve exhaust gas flow while maintaining excellent drivability.

Potential benefits may include:

• Improved Exhaust Gas Flow

• Reduced Exhaust Backpressure

• Sharper Throttle Response

• Enhanced High-RPM Breathing

• More Immediate Engine Character

• Reduced Exhaust System Weight

• Improved Compatibility with Performance Headers

• Optimized Sound When Combined with Performance Exhaust Components

Actual performance gains may vary depending on vehicle configuration and supporting modifications.

Motorsport-Inspired Engineering

The Porsche GT3 was developed with motorsport DNA, and the OAO exhaust system follows the same performance philosophy.

Engineering highlights include:

• High-Flow Straight-Through Muffler Design

• Optimized Pipe Diameter

• Smooth Exhaust Gas Transitions

• Precision Valve Integration

• Reduced Internal Turbulence

• High-Temperature Resistant Construction

• Lightweight Performance Design

• Factory Mounting Compatibility

Every component is designed to balance performance, sound quality, durability, and fitment.

The Sound of a Naturally Aspirated GT3

The Porsche GT3's naturally aspirated flat-six is defined by its linear power delivery and extraordinary high-RPM character.

The OAO Valved Sport Cat-Back enhances that unique personality:

• Deeper Cold Start

• Richer Low-RPM Flat-Six Tone

• Crisp Throttle Blips

• Sharper Acceleration Sound

• Stronger High-RPM Crescendo

• Aggressive Downshift Acoustics

• More Intense Motorsport Character

With the valves fully open, the exhaust note becomes significantly more emotional and immersive, allowing the driver to experience the full character of Porsche's naturally aspirated GT engine.

Premium T304 Stainless Steel Construction

Manufactured from high-quality T304 stainless steel to withstand the demanding conditions of high-performance driving.

Advantages include:

• Excellent Corrosion Resistance

• Superior Heat Resistance

• High Structural Strength

• Lightweight Performance Construction

• Precision TIG Welding

• CNC-Machined Connections

• Long Service Life

• Premium Surface Finish

Each OAO exhaust system is inspected before shipment to ensure precise fitment and consistent manufacturing quality.

Vehicle Fitment

Compatible with:

Porsche 911 GT3 991.1

• 911 GT3 Coupe

• 4.0L Naturally Aspirated Flat-Six

Porsche 911 GT3 RS 991.1

• 911 GT3 RS

• 4.0L Naturally Aspirated Flat-Six

Porsche 911 GT3 991.2

• 911 GT3 Coupe

• 4.0L Naturally Aspirated Flat-Six

Porsche 911 GT3 RS 991.2

• 911 GT3 RS

• 4.0L Naturally Aspirated Flat-Six

Model Years

• 2014–2019

Please verify your vehicle generation, model, production year, and factory exhaust configuration before ordering.

Package Includes

• OAO Valved Sport Cat-Back Exhaust System

• Electronic Valve Control Module

• Wireless Remote Controller

• Exhaust Installation Hardware

• Protective Packaging

Installation

Designed as a direct bolt-on replacement using factory mounting locations.

No permanent cutting or welding is required.

Professional installation is highly recommended to ensure proper alignment, sealing, and valve operation.

Optional Performance Upgrades

The OAO Valved Sport Cat-Back can be paired with:

• OAO Performance Headers

• OAO High-Flow Exhaust Components

• Performance ECU Calibration

• Lightweight Exhaust Components

• Carbon Fiber Exhaust Tips

• Titanium Exhaust Tips

For maximum exhaust flow and sound performance, a complete OAO exhaust setup can be configured according to the vehicle's intended use.

Important Notes

This product is intended for performance, off-road, or motorsport applications where permitted by local regulations.

Please verify local emissions and noise regulations before purchasing or installing this product.

Vehicle compatibility may vary depending on model year, factory exhaust configuration, and regional specification.

Why Choose OAO Performance

OAO Performance specializes in premium exhaust systems for Porsche, Ferrari, Lamborghini, McLaren, Aston Martin, BMW M, Mercedes-AMG, Audi RS, Nissan GT-R, Chevrolet Corvette, and other high-performance vehicles.

Every OAO exhaust system combines precision engineering, premium materials, advanced valve technology, and rigorous quality control to deliver exceptional fitment, durability, and sound.

Upgrade your Porsche 991.1 or 991.2 GT3 / GT3 RS with the OAO Valved Sport Cat-Back Exhaust System and experience a sharper, louder, and more emotional version of Porsche's legendary naturally aspirated 4.0L flat-six.