Kline Innovation Turboback Exhaust System for 991.2 Porsche 911 Turbo S

Kline Innovation Turboback Exhaust System for 991.2 Porsche 911 Turbo S

Embracing its seventh iteration, the 991 turbo version of the iconic 911 has undergone captivating evolutionary advancements. Notable enhancements include a broader wheelbase and improved axel-to-engine geometry, resulting in enhanced weight distribution and cornering stability. The incorporation of additional composites and aluminum materials further contributes to weight reduction, and even the exhaust system has experienced noteworthy improvements compared to its predecessor, the 997. The question arises: How much room is there for further enhancement beyond the factory exhaust? The answer is truly astonishing.

The Sound

• Drawing on the design innovations and achievements of their 996 and 997 range, the company embarked on the development of the 991 turbo exhaust with ambitious goals. The starting point for the design had already been established at an impressive level. Their distinctive x pipe geometry, meticulously tuned silencer geometry, utilization of Inconel 625, and exclusive proprietary acoustic silencer packing materials combined to create a system that had gained widespread acclaim for its exceptional sound quality. With an absence of drone and a captivating, fierce howl at higher RPMs and under aggressive throttle, it had become synonymous with automotive excellence. The design was so impeccable that even catless versions could be driven silently during cruising speeds, reserving their powerful howl for moments of spirited driving.
• Throughout the development process, clear evolutionary design steps emerged and were seamlessly incorporated. The integration of a secondary tail pipe enabled the inclusion of an effective gas overflow system. This concept was conceived during the fluid dynamic modeling phase and effectively reduced low RPM noise while simultaneously increasing the cross section at higher RPMs, resulting in a more pronounced split personality reminiscent of Jekyll and Hyde. Furthermore, it slightly broadened torque curves, enhancing the overall performance experience.

Performance

• The options available include the choice of racing pipes for peak performance and sound, or the selection of 100 or 200 cell HJS HDPE catalysts. Opting for racing pipes yields the most significant power and torque increase, with gains of 38 horsepower and 55 Newton-meters. Meanwhile, the 100 cell and 200 cell catalysts provide power gains of 20 horsepower and 16 horsepower, respectively.

Stainless Steel

• Within the realm of exhaust manufacturing, the prevailing industry norm centers around utilizing 304-grade stainless steel. This specific stainless steel grade offers a well-rounded combination of moderate strength, thermochemical stability, cost-effectiveness, and ease of production. It enables the construction of exhaust systems that strike a sensible balance between affordability and functionality, ensuring long-lasting durability. However, it is important to note that stainless steel is relatively heavier compared to alternative materials. While it shares a similar density with regular steel, it possesses slightly lower tensile strength. This limitation hampers the potential for creating high-performance exhaust components using stainless steel. Furthermore, in terms of sound characteristics, the thicker sidewalls required by stainless steel may result in a somewhat subdued and less vibrant exhaust note compared to the aforementioned materials.

Inconel

• When it comes to ensuring durability and heat resistance in the aerospace industry, the use of Inconel 625 is of utmost importance. This remarkable material finds extensive applications in the manufacturing of critical components, particularly exhaust turbine blades for high-performance jet engines. Notably, Inconel is the preferred choice for Formula One exhaust systems and has been selected by manufacturers engaged in prestigious hypercar projects such as the McLaren P1 and Aston Martin 177. These applications greatly benefit from Inconel’s exceptional ability to withstand extreme temperatures surpassing 1000°C while prioritizing lightweight design.
• Inconel exhibits extraordinary properties, including remarkably high tensile strength and exceptional thermochemical stability. Its tensile strength is comparable to that of titanium, resulting in an outstanding strength-to-weight ratio. Consequently, Inconel allows for the use of thin sidewall materials while maintaining structural integrity, facilitating the production of lightweight components that showcase remarkable resistance to fatigue over extended periods. However, working with Inconel presents certain challenges due to its difficult machinability and specific welding requirements, necessitating specialized skills and time-consuming techniques. Additionally, the unique properties and specialized manufacturing processes associated with Inconel contribute to its higher cost as a raw material.

Carbon Fiber

• Boasting a remarkable tensile strength to weight ratio that surpasses all metals, carbon fiber reinforced polymer showcases exceptional properties. Its lightweight nature, combined with impressive tensile strength, allows for the shaping of components into virtually any desired form. The company exclusively utilizes pre-preg carbon fiber of aerospace and Formula 1 grade, which undergoes a meticulous curing process in an autoclave under high pressure and temperature. This rigorous procedure guarantees the production of carbon fiber that is not only exceptionally strong but also remarkably lightweight, making it the ideal choice for even the most demanding and extreme conditions.

Specifications

• Cross Sections:
  • Racing Pipes Cross Section: 76mm OD (specifically chosen for a balance of peak torque and power)
  • Silencer Section & Cross Section: 70mm OD & 63.5mm OD Overflow
  • Catalysts come in a variety, from 108mm OD to 127mm OD
• Materials:
  • Turbo Back System:
  • 304 Grade Stainless Steel:
    • 200 cell cats: 14kg
    • Racing pipes: 12.5kg
  • Inconel 625 Formula One Grade Material: 7.5kg
  • Manifolds:
    • Standard 304 Grade Stainless Weight: 6kg total
    • Inconel 625 Weight: 2.9kg total
    • Equal length design
  • Tails:
    • Available in Aerospace grade carbon fiber

Applications

• Porsche 911 Turbo S: 991.2 (2016-2019) – 3.8L TT Flat-6

Notes

• The depiction of the manifolds and carbon fiber tips in the images is important to note; however, they are not included in the standard package

About Kline Innovation

At Kline, exhaust design is approached with utmost seriousness. The company adopts a no-compromise stance when it comes to delivering a product that meets the highest standards and satisfies customers’ expectations. Kline offers a comprehensive original equipment design and manufacturing service. Starting from provided drawings or design briefs, the team utilizes advanced 3D modeling techniques to create final designs. They also provide valuable consultation during the process and are capable of manufacturing tooling and fixtures for production, as well as handling final production runs, particularly catering to low to medium volume needs. Kline’s commitment to excellence ensures that customers receive a top-quality product without any compromises.

Development

• All projects at Kline are executed entirely in-house, utilizing a diverse range of processes. These internal capabilities include laser scanning, CNC laser cutting, CNC mandrel bending, tubing and silencer manufacturing, CNC welding, pressings, CNC milling, mould manufacturing, and autoclave carbon fiber production. Notable automotive clients, such as W Motors with their Fenyr Supersport, Corbellati Missile, and RUF Automobil, have recently collaborated with Kline.
• Kline has expanded its design and manufacturing process by incorporating laser scanning capabilities. This valuable addition enables the team to achieve enhanced precision in both design and quality control, resulting in an exceptional end product for customers. The adoption of laser scanning technology at Kline showcases the company’s unwavering dedication to delivering superior outcomes.