Porsche 991.1 Carrera / Carrera 4 3.4L Without PSE SOUL Long Tube Street Headers

Product Description

The SOUL Long Tube Street Headers are designed for Porsche 991.1 Carrera owners looking to improve power, torque, throttle response, exhaust flow, and naturally aspirated flat-six sound while retaining a high-flow catted exhaust configuration.

SOUL replaces the restrictive factory manifold and catalyst assemblies with a purpose-built long-tube header system featuring 2-inch primary runners and large-diameter 300-cell performance catalytic converters.

The 2-inch runner architecture was developed to provide strong exhaust flow while maintaining the gas velocity necessary for responsive street performance. Although SOUL developed the system around the larger Carrera engines as well, it specifically notes that the same design produces strong gains on the 3.4L Carrera engine used in Base 991.1 models.

This DasMotoring listing is specifically intended for 3.4L Carrera models without Porsche Sport Exhaust / PSE, allowing owners to retain their factory non-PSE rear exhaust while substantially improving the upstream exhaust system.

FITMENT:

• Fits 2012–2016 Porsche 991.1 911 Carrera Coupe – 3.4L – Without PSE

• Fits 2012–2016 Porsche 991.1 911 Carrera Cabriolet – 3.4L – Without PSE

• Fits 2012–2016 Porsche 991.1 911 Carrera 4 Coupe – 3.4L – Without PSE

• Fits 2012–2016 Porsche 991.1 911 Carrera 4 Cabriolet – 3.4L – Without PSE

• Fits applicable 991.1 Targa 4 3.4L models without PSE

• Compatible with factory non-PSE rear exhaust systems

• Compatible with applicable SOUL rear exhaust upgrades

• Compatible with manual and PDK-equipped vehicles where applicable

• Porsche Sport Exhaust / PSE is not required

• SOUL specifies the physical header assembly for the broader 991.1 Carrera platform, while this DasMotoring listing is specifically categorized for the Base 3.4L without PSE

DETAILS:

• Direct-replacement Long Tube Street Header upgrade

• Developed specifically for the Porsche 991.1 Carrera platform

• 2-inch primary runners

• Long-tube architecture designed to improve exhaust scavenging

• Specifically documented by SOUL to provide strong gains on the 3.4L Carrera engine

• Large-diameter, free-flowing catalytic converters

• SOUL-designed 300-cell performance catalytic converters

• Custom-specified precious-metal catalyst coating

• Triple-metal-matrix catalyst-core construction

• Designed to increase exhaust flow

• Improves throttle response

• Improves low- and midrange torque

• Improves high-RPM breathing

• Produces stronger naturally aspirated flat-six sound

• Engineered to avoid catalyst-related check engine lights under normal operating conditions

• Merge spikes incorporated into the collector architecture

• Merge spikes help guide exhaust gases smoothly as the primary runners converge

• Constructed from T304L stainless steel

• Thick water-jet-cut exhaust flanges

• Flanges manufactured to ISO 9001:2015 standards

• Each header assembly is built in a thick-gauge aluminum fixture

• Fixtures help minimize distortion during welding

• Each assembly undergoes fitment and quality-control checks

• New high-grade header-to-exhaust flange hardware included

• Direct bolt-on installation

• Designed and manufactured in-house by SOUL Performance Products in Willow Grove, Pennsylvania

• Backed by SOUL's Lifetime Warranty for street and track use

DESIGNED FOR THE 3.4L CARRERA:

The 991.1 Carrera Base uses Porsche's naturally aspirated 3.4-liter flat-six, making exhaust scavenging and gas velocity particularly important.

Unlike a turbocharged engine, the 3.4L cannot compensate for a restrictive exhaust system simply by increasing boost pressure.

SOUL's 2-inch long-tube header architecture is designed to improve the engine's ability to evacuate exhaust gases while maintaining strong gas velocity.

Potential benefits include:

• Improved low-RPM response

• Increased midrange torque

• Sharper throttle response

• Improved high-RPM breathing

• Stronger acceleration through the usable rev range

• Greater naturally aspirated engine character

2-INCH LONG-TUBE RUNNERS:

Header diameter is a compromise between outright flow capacity and exhaust-gas velocity.

Tubing that is too small can become restrictive as engine speed and exhaust flow increase.

Tubing that is excessively large can reduce gas velocity and weaken scavenging, particularly at lower engine speeds.

SOUL selected 2-inch primary runners to provide substantial flow capacity while preserving the exhaust velocity required for responsive street performance.

The long-tube architecture also allows the runner length and collector placement to be optimized more effectively than the compact factory manifold arrangement.

300-CELL PERFORMANCE CATALYSTS:

The Street Headers retain catalytic converters rather than converting the vehicle to a completely catless configuration.

SOUL currently specifies:

300-cell performance catalytic converters

featuring:

• Custom-specified precious-metal coating

• Triple-metal-matrix catalyst construction

• High-flow architecture

• Reduced restriction compared with the factory catalyst assemblies

This provides a useful compromise between the exhaust-flow advantages of aftermarket headers and the refinement of a catted system.

MERGE COLLECTOR DESIGN:

The individual header runners feed into purpose-designed collectors containing merge spikes.

The merge spikes help control the transition as the individual exhaust streams converge.

Rather than allowing the gases to collide abruptly inside the collector, the geometry is intended to guide flow smoothly into the downstream exhaust.

Collector design influences:

• Exhaust scavenging

• Gas velocity

• Throttle response

• Midrange torque

• High-RPM breathing

• Exhaust sound

This is particularly relevant on a naturally aspirated engine where exhaust pulse behavior plays an important role in cylinder evacuation.

DYNO-PROVEN PERFORMANCE:

SOUL independently tested the 991.1 Long Tube Street Headers on a Mustang dynamometer.

The reported results include approximately:

+9 wheel horsepower at peak power

+13 lb-ft of torque at peak torque

More importantly, substantially larger gains were recorded through portions of the usable RPM range.

SOUL reports improvements exceeding approximately:

+25 wheel horsepower

and

+25 lb-ft of torque

around 3,000 RPM.

That means the most noticeable benefit is not necessarily the headline peak-horsepower number.

The stronger improvement through the low- and midrange should be particularly noticeable during normal street driving, corner exits, highway acceleration, and situations where the driver rolls into the throttle without immediately downshifting.

LOW- & MIDRANGE PERFORMANCE:

For a street-driven Carrera, improving the shape of the power curve can be more useful than increasing only the maximum horsepower figure.

The long-tube headers produce meaningful gains in the RPM range the engine frequently operates within during normal driving.

Expect:

• Stronger response from lower engine speeds

• Increased midrange torque

• More immediate acceleration

• Reduced feeling of restriction as RPM rises

• Greater urgency from the 3.4L engine

• Improved response without requiring an ECU tune

ECU TUNING:

An ECU calibration is not required simply to install the SOUL Long Tube Street Headers.

The headers and high-flow catalytic converters are designed to operate as a bolt-on upgrade on otherwise properly functioning vehicles.

SOUL notes, however, that additional gains may be available with appropriate ECU calibration.

This is particularly relevant above approximately 5,000 RPM, where ignition timing and other calibration changes can take greater advantage of the improved exhaust flow.

SOUND CHARACTER:

The Long Tube Street Headers increase exhaust character without automatically turning the vehicle into an extremely loud system.

With the factory non-PSE rear exhaust retained, expect:

• Deeper naturally aspirated flat-six tone

• Greater exhaust presence under load

• More mechanical engine character

• Stronger high-RPM sound

• Increased intensity approaching redline

• More audible exhaust response to throttle inputs

• Greater overall engine character without replacing the factory rear mufflers

The exact final sound will depend heavily on the rear exhaust installed downstream.

WITH FACTORY NON-PSE REAR EXHAUST:

These headers can be installed while retaining the factory Base Carrera non-PSE rear exhaust system.

This configuration provides:

• Improved upstream exhaust flow

• 300-cell performance catalysts

• Increased power and torque

• Sharper throttle response

• Stronger flat-six sound

• Retention of the quieter factory non-PSE rear mufflers

• No need to convert the vehicle to Porsche Sport Exhaust

This makes the Street Headers particularly appealing for owners who want a meaningful performance upgrade without making the rear exhaust dramatically louder.

PSE IS NOT REQUIRED:

Porsche Sport Exhaust is not required for installation.

The headers sit upstream of the rear mufflers and are not dependent on whether the vehicle was originally equipped with PSE.

There is therefore no separate PSE versus non-PSE header version.

The same SOUL header architecture can work with multiple compatible rear-exhaust configurations.

This DasMotoring listing is simply organized specifically for customers shopping under the 991.1 Carrera Base Without PSE category.

CHECK ENGINE LIGHT:

SOUL developed the Street Headers and their high-flow catalysts to provide increased exhaust flow while avoiding catalyst-related check engine lights under normal operating conditions.

As with any aftermarket catalyst system, diagnostic behavior can still be influenced by:

• Oxygen-sensor condition

• Existing engine faults

• Fuel quality

• ECU software

• Additional exhaust modifications

• Catalyst condition

• Vehicle mileage and maintenance history

The system should therefore not be interpreted as an unconditional CEL guarantee under every possible vehicle condition.

STREET HEADERS VS. COMPETITION HEADERS:

Long Tube Street Headers

• 300-cell performance catalytic converters

• Street-oriented configuration

• Significant increase in exhaust flow

• Strong low- and midrange gains

• Retain a catted exhaust system

• Designed around normal factory ECU operation

• Compatible with the factory non-PSE rear exhaust

• $4,855.00

Competition Headers

• Catless

• Maximum available header flow

• Greater exhaust volume

• More aggressive character

• Greater emissions and diagnostic considerations

• More competition-oriented configuration

The Street Headers are the more appropriate choice for customers looking for a substantial performance improvement while retaining catalytic converters.

EMISSIONS NOTE:

The SOUL Long Tube Street Headers retain catalytic converters but replace the original Porsche catalyst assemblies with aftermarket performance components.

They are not CARB certified.

Customers are responsible for determining compliance with applicable federal, state, and local regulations before installation or use.