Porsche Cayenne Turbo S / GT / GTS – EPA-Compliant 400 Cell Catted Downpipes

Precision Engineered for the 4.0L Twin-Turbo V8 • High-Flow Performance •

Introducing Our NEW 400 Cell EPA-Compliant Downpipes for Cayenne

The Porsche Cayenne Turbo platform is a masterclass in performance engineering. However, factory catalyst restrictions limit the full efficiency and character of its 4.0L twin-turbo V8. Our NEW EPA-compliant 400 cell high-flow catted downpipes are engineered to reduce exhaust restriction, improve turbo response, and refine the exhaust note — all while maintaining emissions compliance standards.

Designed specifically for the Cayenne Turbo S, Turbo GT, and GTS, these downpipes elevate the driving experience while preserving the precision Porsche is known for.

Why 400 Cell?

• EPA-Compliant 400 Cell High-Flow Catalysts: Increased exhaust efficiency while maintaining compliance standards.
• Improved Turbo Response: Reduced backpressure sharpens throttle input and mid-range delivery.
• Refined Yet Aggressive Sound: Deeper tone with enhanced clarity at higher RPM.
• Maintained Daily Comfort: Performance gains without sacrificing drivability.

Engineering & Performance

• Optimized Flow Design: Reduces restriction while preserving catalyst efficiency.
• Mandrel-Bent Tubing: Smooth internal transitions for consistent exhaust velocity.
• Precision TIG Welding: Built to endure high temperatures and sustained boost pressure.
• Direct OEM Bolt-On Installation: Utilizes factory mounting locations.
• Engineered to Pair with Valvetronic Exhaust Systems

Sound Profile

• Stock Exhaust + Downpipes: Noticeable increase in depth and presence without overwhelming cabin refinement.
• Valvetronic Exhaust + Downpipes: Sharper response, increased volume, and a more motorsport-inspired character while retaining Porsche composure.

Construction & Durability

• Premium high-grade stainless-steel construction
• High-temperature resistant 400 cell catalyst cores
• OEM-style sensor placement for proper operation
• Engineered for long-term reliability under high performance conditions

Elevate the performance and sound of your Porsche Cayenne — engineered with precision, starting at the source.

📩 Questions or ordering assistance? customerservice@valvetronic.com

Valvetronic Designs shipping & returns

• Returns: new, unused and uninstalled parts within 30 days of purchase, in the original packaging, with a return authorization (RMA) number issued first.
• Restocking fee: 25% on all non-warranty returns; the customer pays return shipping unless the part qualifies for warranty.
• Sound: exhaust sound and tone are personal taste and are not grounds for a return or warranty claim.
• Warranty: lifetime on stainless and titanium tubes and welds, 3 years on mufflers and resonators, 1 year on valves, remotes, electronics and tips. If a problem shows up after install, contact us before removing the part.

To start a return or ask a question, contact us with your order number.