Kooks 2015+ Ford Mustang GT350 5.2L 3in x 2-3/4in Cat SS X-Pipe Kooks HDR Req

Kooks 3" GREEN Catted Connection Pipes for 2015 and 2020 Ford Mustang Shelby GT350 / GT350R 5.2L Voodoo

The Kooks 11543200 3-inch GREEN catted connection pipes complete the exhaust upgrade on 2015 and 2020 Shelby GT350 and GT350R models with the 5.2L Voodoo V8, linking Kooks long tube headers directly to the factory mid-pipe for seamless integration that maintains 49-state emissions compliance while adding 20 and 30 rear-wheel horsepower and 25 and 35 lb-ft of torque through high-flow 300-cell metallic substrate GREEN catalytic converters and mandrel-bent tubing.

Handcrafted from T304 aircraft-quality stainless steel with 3/8-inch laser-cut flanges and full TIG welds, these pipes ensure zero leaks under extreme heat and support over 850 HP from tunes or supercharger kits without sacrificing ground clearance or daily drivability. The design preserves the GT350’s iconic flat-plane crank scream while delivering a deeper, more aggressive tone at wide-open throttle and refined quietness at cruise.

For Shelby GT350 owners pairing Kooks headers with stock exhaust, the 11543200 GREEN catted connection pipes are the essential emissions-legal link that maximizes Voodoo performance with track-proven reliability.

Key Features

• 3-inch mandrel-bent T304 stainless steel tubing
• GREEN 300-cell high-flow metallic catalytic converters
• Direct bolt-on to Kooks headers and OEM mid-pipe
• 3/8-inch laser-cut flanges with full TIG welds
• Supports 850+ HP with proper tuning
• Preserves factory heat shielding and ground clearance

Product Notes

• 49-state EPA compliant not for sale or use in California or CARB states without exemption
• Requires Kooks long tube headers for proper fitment
• Includes all hardware and gaskets

California Proposition 65: Contains chemicals known to the State of California to cause cancer or reproductive harm.

Warranty: Limited lifetime on stainless construction and 25,000 miles on catalytic converters to original purchaser.

Installation Notes

• Professional installation recommended lift required
• Bolt pipes to Kooks header collectors with supplied gaskets
• Connect to OEM mid-pipe using included hardware
• Torque flanges to 25-30 ft-lbs and check for leaks after heat cycle

This Part Fits

Note: Fits all 2015 and 2020 Shelby GT350 & GT350R with Kooks long tube headers. Manual transmission only.

What's Included in the Purchase

• (2) 3" GREEN Catted Connection Pipes
• Gaskets and Flange Hardware Kit
• Detailed Installation Instructions
• Part Number: Kooks 11543200

Why Choose Kooks?

• Over 60 years of championship-winning exhaust engineering
• Handcrafted in the USA from T304 aircraft-quality stainless steel
• Limited lifetime warranty and dyno-proven performance

Frequently Asked Questions

• Q: Does this work with factory headers?
  A: No, designed specifically for Kooks long tube headers
• Q: Is it emissions legal?
  A: Yes, 49-state EPA compliant with GREEN cats
• Q: How loud is it?
  A: Aggressive flat-plane scream at WOT, refined at cruise
• Do Kooks headers require a tune after installation?
  Yes. A professional tune is strongly recommended after installing long tube headers. The significant improvement in exhaust flow changes air fuel ratios and requires ECM recalibration to achieve optimal power output and safe operation.
• Will these headers void my factory powertrain warranty?
  Under the Magnuson-Moss Warranty Act, a manufacturer cannot void your vehicle warranty simply because you installed an aftermarket part unless they prove the component directly caused the failure. Consult your dealer for specifics on your situation.
• Q: Do these Kooks headers require a tune after installation?
  A: Yes. A professional tune is strongly recommended after installing long tube headers. The significant improvement in exhaust flow changes air fuel ratios and requires ECM recalibration to achieve optimal power output and safe operation.
• Q: Will Kooks headers void my factory powertrain warranty?
  A: Under the Magnuson-Moss Warranty Act, a manufacturer cannot void your vehicle warranty simply because you installed an aftermarket part unless they prove the component directly caused the failure in question. Consult your dealer for specifics.
• Q: What warranty does Kooks provide?
  A: Kooks products are backed by a limited lifetime warranty to the original purchaser against defects in materials and workmanship. Racing and competition use applications may have specific warranty exclusions. Contact Kooks Performance directly for warranty details.

Shipping & Handling

• Method: UPS or Fed Ex Ground.
• Availability: Typically ships same day or next if in stock.
• Packaging: Heavy-duty box with foam protection.