Description
Many owners are underwhelmed with their 991.1 Carrera’s sport exhaust sound and performance – it’s just not enough. We’ve set out to create an exhaust with a true Jekyll and Hyde personality that matches perfectly with the persona of the Carrera – a wolf in sheep’s clothing. Our first priority was to design the system so that with valves open, exhaust gases would have a straight flow path. By using a larger tubing diameter, smooth radius bends and proper X-pipe crossover flow characteristics (improving exhaust scavaging effects, leading to increased volumetric efficiency), our system improves throttle response and performance drastically over the restrictive factory sport exhaust.
DEVELOPMENT AND TESTING: Our aim was to refine the level of daily driving comfort without sacrificing the race inspired tone and straight-through exhaust design. A larger resonator would not yield the results we are looking for while requiring some revisions for clearances – this could compromise the high flow design principles of our exhaust. Adding higher flowing aftermarket headers – like our Long Tube Street Headers – to an aggressive rear system without proper sound attenuating features could result in a overly loud, possibly unpleasant driving experience. Nearly 40% of our customers paired their rear exhaust with upgraded headers making it imperative that we consider such a configuration and engineer the exhaust appropriately. Helmholtz resonators (also known as anti-drone tubes) are an effective way to reduce undesirable frequencies when engineered and utilized correctly. The 991.1 Carrera has an inherent 3,000-3,500 RPM range where drone can present itself when you add higher flowing exhaust components. Our goal was to filter out the undesirable frequencies in that range while smoothing the valves closed to open transition on factory PSE equipped cars. Our Long Tube Street Headers increase volume to an enjoyable level while adding more response and power to turn your Porsche into a true drivers car! For the base model, we devised a solution to allow for retaining the factory side mufflers – simply cut the factory side mufflers and clamp on the included secondary pipes which connect the side mufflers to the exhaust tips
Our final design has proved to offer the very best results on this application and achieved our high standards for sound quality and drivability. The math can be done to create the Helmholtz resonators – but how you incorporate them into your design makes a big difference.
SOUND: The sound is aggressive – a primary benefit of our system is that with valves open there is straight, unrestricted path from the 2.5″ piping to the tips – but we’ve effectively massaged extra refinement into the system to match the premium experience that embodies all things Porsche. With valves both open and closed the X-pipe helps smooth the sound even further. All in all, we’re very happy with the results and we’re sure you will be too! With valves open, the free flowing nature of the system allows for a Cup car inspired sound – greater volume with a greater amount of crackles and burbles on deceleration. This system is for those who want added aggression at the press of a button. With valves closed the tone is very reasonable and refined, drone is kept to a minimum while still allowing for the flat six sound to be heard.
CONSTRUCTION: Each 991.1 Carrera component is built in house out of mandrel bent, thick wall .065″” T304L stainless steel, then rigorously quality checked. Back purged TIG welding ensures proper weld penetration and longevity. Merge spikes are incorporated into the headers to smooth exhaust flow into the collector and increase power. Thick water jet cut flanges cut to ISO 9001:2015 standards ensure perfect fitment and product longevity.
HJS CATALYSTS: The highest quality catalytic converters available, known for their industry leading flow and durability. They are efficient enough to meet strict EURO 4 emission standards while still allowing for an increase in flow – all without a check engine light. The HD design uses premium triple foil winding for maximum strength. The brazing stripe is an extra feature in the interest of durability – it prevents the core from moving or experiencing any damage from sustained high horsepower abuse. We use a large and appropriately sized catalyst to allow for maximum gains – no compromises here!
BOLT ON AND GO: Each exhaust is tested in a fixture to ensure perfect fitment and then foam packed to arrive in perfect condition. Thorough installation instructions are included in the box for a straightforward install that can be performed by most DIY enthusiasts. New high grade hardware is included. This system works seamlessly with the factory PSE controls but can also be used on non PSE equipped S / GTS cars by installing a SOUL valve controller kit.
LIFETIME WARRANTY: Enjoy your SOUL exhaust components with confidence on both the street and track as they are covered by our Lifetime Warranty! Our team will quickly work with you to resolve any issues or answer any questions that you may have.
NOTES:
- Installation of the valve controller requires removing rear bumper, locating and tapping a 12V switched power source, and installing vacuum lines. We highly recommend professional installation for this Porsche exhaust system. For recommendations of your nearest SOUL parts installer, please contact us.
- Cutting of the factory side mufflers is required to incorporate included piping to tips.
Tempus fugit (Rennlist) –
My local indie (Eurohaus in Lenoir City TN) installed the Soul sport headers and switchable exhaust installed on my 991.1 4S about a month ago and it puts a smile on my face every time I start it up. I did not have PSE so the change was very dramatic. I agree with others who said the system is fairly loud and aggressive compared to stock. To me, the sound with the valve open is glorious, but there are times when I want a quieter car, so the switchable feature of this exhaust system was a must. When my wife is riding with me or I want to listen to media I have the valve closed (mufflers active), but most of the time the valve is open so I can enjoy the engine sound.
I was initially hesitant to order it having never heard one in person, but the many positive reviews and the explanation I received from the nice folks at Soul about how the system would work on my non-PSE car convinced me that this was the right system for my car. Eurohaus did a fantastic installation job and it was the first Soul exhaust they’d installed. The Soul build quality, performance and reputation of the company impressed them enough that they became a Soul dealer.
John H –
Some random thoughts about the system on the drive home:
· It was really hard not to stomp on the gas so I could hear the great sound
· It was slightly louder / deeper than PSE with the valves closed at normal (meaning social accepted) driving speeds / acceleration but not “bad” and -as I said earlier – no drone
· At freeway speed, with the valves open and not on cruise control it seemed fine – more gas, more noise – just what I would expect
· With valves open, at 2,000 rpm (75mph) and on cruise control the resonance does start to get a bit noticeable – it seemed that the cruise control managing the acceleration made it worse – it was easy to fix – just close the valves and everything was the same as it was before the conversion
· Bottom line – basically the same as PSE with valves closed … and way – way – way better than PSE with the valves open
In terms of the new long tube high flow headers over the stock headers:
· I know that the headers helped the sound quality a lot
· On the drive home on the freeway driving at socially acceptable speeds / acceleration, I can’t unequivocally say that I noticed a big difference in performance – the car always seemed quite quick to me “out of the box” – especially with the Softronic tune – and while I accept the fact that the headers may have increased the hp, I just could not tell that there was a big improvement
· Driving on some back roads around town where I could ignore social norms and let the car “stretch it legs”, it sure seems like it has a lot more acceleration in the mid and upper rpm range – I guess there is a slight chance that is just due to the awesome sound and that is influencing my sense of speed – for whatever reason it sure seems a lot more responsive running it at max shift points.
Now it has been installed since Spring and the sounds is only getter better — deeper and even more raw!