Kline Innovation Turboback Exhaust System for 991.2 Porsche 911 Turbo S Exclusive Series

Kline Innovation Turboback Exhaust System for 991.2 Porsche 911 Turbo S Exclusive Series

The 991 turbo exclusive, boasting an unprecedented 607 horsepower, was in desperate need of an F1-grade Inconel exhaust upgrade, making it the most formidable and distinctive 911 ever.

The Sound

• Capitalizing on the design innovations and successes of their 996 and 997 range, the company set the bar high when it came to designing the 991 turbo exhaust. The focal point was their signature perfect x pipe geometry, harmonically tuned silencer geometry, utilization of Inconel 625, and the implementation of proprietary acoustic silencer packing materials. This combination resulted in a system that had become renowned for its impeccable sound quality. It boasted zero drone and emitted a captivating, raucous howl at higher RPMs and during intense throttle. Such was the perfection of the design that even the catless versions ran silently at cruising speeds, with the full force of the howl unleashed only when the car was driven hard.
• Throughout the development process, the team identified clear evolutionary design steps that could be incorporated. One of these steps was the integration of a secondary tail pipe, which served as an effective gas overflow system. This concept was conceptualized during the fluid dynamic modeling stage and proved successful in reducing low RPM noise while simultaneously increasing the cross section at higher RPMs, resulting in a more pronounced Jekyll and Hyde personality and slightly broader torque curves.

Performance

• Customers have the choice between equipping their vehicle with racing pipes for maximum performance and sound, or opting for 100 or 200 cell HJS HDPE catalysts. Racing pipes offer the most significant power and torque enhancement, with a remarkable increase of 38 horsepower and 55 Newton-meters. Alternatively, selecting the 100 cell or 200 cell catalysts yields power gains of 20 horsepower and 16 horsepower, respectively.

Stainless Steel

• Within the domain of exhaust manufacturing, the prevailing industry norm centers around the utilization of 304-grade stainless steel. This particular stainless steel grade offers a harmonious blend of moderate strength, thermal and chemical 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 acknowledge that stainless steel is relatively heavier when compared to alternative materials. Despite sharing a similar density with regular steel, it possesses slightly lower tensile strength. This characteristic limits the potential for creating high-performance exhaust components using stainless steel. Additionally, in terms of sound characteristics, the thicker sidewalls required by stainless steel may result in a somewhat muffled and less dynamic exhaust note in comparison to the aforementioned materials.

Inconel

• When it comes to ensuring durability and heat resistance in the aerospace industry, Inconel 625 takes the lead. This remarkable material is extensively employed in the production 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 involved in prestigious hypercar projects like the McLaren P1 and Aston Martin 177. These applications greatly benefit from Inconel’s exceptional ability to withstand extreme temperatures exceeding 1000°C, all while prioritizing lightweight design.
• Inconel possesses 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 enables the use of thin sidewall materials while maintaining structural integrity, facilitating the production of lightweight components that exhibit remarkable resistance to fatigue over prolonged 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.

Specifications

• Cross Sections:
  • Racing Pipes Cross Section: 70mm 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:
    • 200cell cats: 14kg
    • Racing pipes: 12.5kg
  • Inconel 625 Formula One Grade Material: 7.5kg
• Manifolds:
  • Standard 304 Grade Stainless: 6kg total
  • Inconel 625: 2.9kg total

Applications

• Porsche 911 Turbo S Exclusive Series: 991.2 (2017-2019) – 3.8L TT Flat-6

Notes

• Although the images display the manifolds, it is crucial to mention that 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, mold 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.