Kooks Headers 21613321 3" Green Catted Ultra X-Pipe for C6 Z06/ZR1 LS7/LS9

The Kooks Headers 21613321 is a 3" Green Catted Ultra X-Pipe engineered for the LS7 and LS9 powerplants found in the C6 Z06 and ZR1. This upgraded ULTRA X configuration uses a full-length Long Merge design to improve exhaust pulse scavenging, enhance top-end power output, and deliver the distinctive X/H-inspired exhaust tone that performance Corvette enthusiasts demand.

At the heart of this system are Kooks' proprietary GREEN high-flow catalytic converters, which are rated to support up to 750 RWHP — compatible with both naturally aspirated and boosted applications. The GREEN cat coating incorporates additional precious metals to function properly in high-heat, high-horsepower environments while delivering a refined, balanced exhaust note without excessive rasp.

Constructed from mandrel-bent 3" T304 aircraft-grade stainless steel with CNC-built precision, this system connects directly to 3" OEM (Z06/ZR1-style) rear exhaust systems and interfaces with Kooks Long Tube Headers via included front connections. All Kooks products are handcrafted in the USA and backed by a limited lifetime warranty to the original purchaser.

Key Features:

• GREEN Catted ULTRA X design for improved performance and refined exhaust tone
• Full-length Long Merge for enhanced exhaust pulse scavenging and top-end power
• HIGH-flow GREEN catalytic converters rated up to 750 RWHP (boosted or N/A)
• Mandrel-bent 3" T304 stainless steel tubing for optimized flow and durability
• CNC-built construction for precision fitment and consistent quality
• Includes front connections for direct interface with Kooks Long Tube Headers
• Connects to 3" OEM (Z06/ZR1-style) rear exhaust systems
• Handcrafted in the USA — limited lifetime warranty to the original purchaser

Important Notes: Requires Kooks Long Tube Headers — does not fit OEM exhaust manifolds. Not legal for sale, installation, or use on a licensed vehicle in the State of California.