Kline Innovation Valvetronic Exhaust System for 991.2 Porsche 911 GT3 (OPF)

The Kline Innovation Exhaust System for the Porsche 991.2 GT3  is a high-performance valvetronic exhaust developed to give the naturally aspirated flat-six engine the race-inspired sound and performance it deserves. Drawing on the formidable heritage of the 911 GT3 platform with power output over 475 hp and a 9,000 rpm redline — Kline engineers apply their proven formula of F1-grade Inconel 625, tuned cross-sections, and optimized x-pipe geometry to deliver a system that is lightweight, durable, and sonically exhilarating. When the valves are closed the exhaust remains refined and comfortable with tuned silencers reducing unwanted drone, and when opened the system frees the exhaust flow for a dramatic, race-car-like scream that enhances the character of the GT3. Designed for precision fitment and uncompromising quality, this upgrade compliments the dynamic performance of the Porsche 911 991.2 GT3 while providing a transformative driving experience on both road and track

The Sound

• The sound journey begins at the manifolds, where replacing the stock cats with 100-cell, or long-tube catless Inconel headers notably amplifies the sound. The gases then flow through one of two channels. When the valve is closed, the gases travel through harmonically tuned, internally ceramic insulated wing silencers, effectively removing unwanted drone during highway cruising, and into the center muffler, before reaching the trademark 1D CLR x pipe. This configuration ensures a very civilized sound when required.
  When the valve is open, both the wing and center silencers are entirely bypassed, allowing the gases to move freely through the exhaust system. The distinctive geometry of the 1D CLR X pipe significantly elevates the pitch of the exhaust into a raucous yet harmonious, incendiary scream, without obstructing the gas flow. The Inconel 625 material also contributes a unique sound, further enhancing the natural sound of the exhaust system. The thin sidewall resonates to generate an even higher pitched scream at high revs.

Performance

• The most significant performance boost comes from replacing the catalysts in the stock headers. The headers and full system are designed to work in harmony for optimal performance and sound. The system and headers are available in two options, 100 cpsi catalysts producing a maximum gain of 18 hp and 27nm, or racing long-tube headers offering a maximum gain of 24hp and 35nm.

Stainless Steel

• Within the exhaust manufacturing industry, 304-grade stainless steel is commonly chosen due to its decent strength, thermochemical stability, cost-effectiveness, and fabrication convenience. Nonetheless, while stainless steel is fitting for constructing sturdy exhaust systems, it is denser than other materials. Its density mirrors that of standard steel, but its tensile strength is somewhat lacking, limiting its potential for high-performance exhaust parts. Also, the need for thicker walls in stainless steel might result in a more muted and less vibrant exhaust sound.

Inconel

• Inconel 625 is held in high esteem within the aerospace industry for its robustness and heat resistance. It is prevalently used in the creation of vital parts, notably exhaust turbine blades for high-performance jet engines. Inconel is a favorite in Formula One exhaust systems and has been selected by manufacturers for elite hypercar projects, such as the McLaren P1 and Aston Martin 177. Capable of withstanding temperatures above 1000°C, Inconel prioritizes a lightweight design. However, Inconel poses unique challenges due to its difficult machinability and specific welding requirements, necessitating specialized skills and complex techniques.

Carbon Fiber

• Carbon fiber reinforced polymer, which possesses a tensile strength-to-weight ratio that outperforms all metals, demonstrates exceptional properties. Its lightweight nature combined with remarkable strength makes it a favored material in various industries, including automotive and aerospace. Carbon fiber components contribute to weight reduction and provide improved rigidity, thereby enhancing overall vehicle dynamics.

Specifications

• Materials:
  • Inconel 625:
    • Racing Manifolds: 2.3kg each
    • Wing Silencers: 4.6kg each
    • Center Silencer with Tips: 5.9kg each
    • Total Weight Manifold Back: 15.1kg
    • Total Weight Incl. Manifolds: 19.7kg (19.2kg Weight Saving)
  • 304 Grade Stainless Steel:
    • Manifolds: 4kg each
    • Wing Silencers: 8.5kg each
    • Center Silencer with Tips: 10.5kg
    • Total Weight Manifold Back: 27.5kg
    • Total Weight Incl. Manifolds: 35.5kg
• Cross Sections:
  • All cross section have been selected for a balance of peak torque and power
• Manifolds:
  • Primaries: 51mm
  • Secondaries: 70mm
• Rear Section:
  • Valve Open: Tapered 70mm Into 63.5mm X-Pipe
  • Valve Closed: 57mm Into Wing Silencers

Applications

• Porsche 911 GT3 | 991.2 | 2017-2019 | 4.0L Flat-6

Notes

• It’s crucial to note that while the images prominently feature manifolds and carbon fiber tips, these components 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.