Kooks 18-24 Ford Mustang GT 5.0 3in. Valved Shotgun Cat-Back Exhaust - Carbon Tips

Transform Your S550 Mustang GT Sound and Performance with a Valved Shotgun Cat-Back and Quad Carbon Fiber Tips

The Kooks 11514520 is a complete OEM x 3 inch valved shotgun cat-back exhaust system built for the 2018 through 2024 Ford Mustang GT 5.0L 4V Coyote V8 on the S550 platform. MPN 11514520 replaces the factory cat-back section with a T304 stainless steel system featuring a 2-1/4 inch x 3 inch H-pipe, 3 inch mid pipes, 3 inch rear pipes, shotgun-style valved muffler sections, and quad carbon fiber exhaust tips. The valve system on the 11514520 allows the driver to switch between a refined, subdued tone for daily driving and an aggressive, full-throttle exhaust note for spirited acceleration, all without removing or replacing any components. Designed and built to order at Kooks' USA facility, the 11514520 is compatible with the 2018 through 2024 Mustang GT, GT Premium, and California Special on the S550 platform.

The Kooks 11514520 is designed to connect directly to the OEM headers and OEM mid-pipe on the 2018 through 2024 Mustang GT 5.0L, making it a direct bolt-on cat-back upgrade that requires no cutting, welding, or custom fabrication. This system is intended for the Mustang GT with the 5.0L 4V Coyote engine and is NOT designed for the GT350, GT350R, GT500, Mach 1, EcoBoost, or any other Mustang variant with different exhaust routing or outlet configuration. The lead time on the 11514520 is 4 to 6 weeks as each unit is hand-built to order in the USA. Kooks backs this system with a limited lifetime warranty on all stainless steel components.

Key Features

• Valved Shotgun Muffler Sections: Driver-controlled exhaust valve system transitions from a civilized daily-driver tone to a thunderous wide-open sound at the push of a button or with the included remote, keeping the neighborhood happy and the track loud.
• Quad Carbon Fiber Tips: Four carbon fiber exhaust tips deliver a premium, race-inspired aesthetic that complements the S550 Mustang GT's rear fascia without overpowering the factory diffuser design.
• 2-1/4 Inch x 3 Inch H-Pipe: The crossover H-pipe balances exhaust pulses between cylinder banks, producing a broad torque curve and a smooth, even exhaust note across the entire RPM range.
• 3 Inch Mid Pipes and 3 Inch Rear Pipes: Full 3 inch diameter pipe routing from the OEM mid-pipe connection through the rear valance eliminates the factory flow restriction and supports power gains from camshaft, intake, or forced induction upgrades.
• T304 Stainless Steel Construction: Aircraft-quality stainless throughout the system resists corrosion, saltwater exposure, and sustained exhaust temperatures without discoloring or pitting over time.
• Direct OEM Bolt-On Fitment: Connects to the factory OEM headers and mid-pipe on the 2018 through 2024 Mustang GT 5.0L without any modification to existing components.
• Handcrafted in the USA: Every 11514520 is built to order at Kooks' American facility with the same race-proven quality control applied to every Kooks exhaust product.
• Compatible with S550 GT, GT Premium, and California Special: Engineered to fit all standard 5.0L Coyote GT variants on the S550 platform from 2018 through 2024.

What's Included

• 2-1/4 inch x 3 inch T304 Stainless Steel H-Pipe
• 3 inch T304 Stainless Steel Mid Pipes, Left and Right
• 3 inch T304 Stainless Steel Rear Pipes, Left and Right
• Shotgun Valved Muffler Sections with Valve Actuators
• Quad Carbon Fiber Exhaust Tips
• Valve Control Module and Wiring Harness
• Mounting Hardware, Clamps, and Hangers
  

Product Specifications

This Part Fits

Frequently Asked Questions

Q: Will the Kooks 11514520 fit my 2018 through 2024 Mustang GT without modifying the factory mid-pipe?
A: Yes. The 11514520 is designed as a direct bolt-on cat-back replacement that connects to the OEM mid-pipe on the 2018 through 2024 Mustang GT 5.0L. No cutting, welding, or modification of the OEM mid-pipe is required.

Q: How does the valve system work on the Kooks 11514520 shotgun cat-back?
A: The 11514520 uses electronically actuated exhaust valves inside the shotgun muffler sections. The included valve control module and wiring harness allow the driver to switch between a quiet, refined tone for neighborhood and daily driving and a full, aggressive sound for performance driving. The system is driver-controlled and does not require a tune to operate.

Q: Is the Kooks 11514520 compatible with the GT350, GT500, or Mach 1 Mustang?
A: No. The 11514520 is designed exclusively for the 2018 through 2024 Mustang GT with the 5.0L 4V Coyote V8 on the S550 platform. The GT350 and GT350R use a flat-plane crank 5.2L Voodoo engine with different exhaust routing, and the GT500 uses a supercharged 5.2L with its own unique system. The Mach 1 has different mid-pipe geometry. Do not use this part on those variants.

Q: Do I need a tune after installing the Kooks 11514520 cat-back?
A: A tune is not required for the 11514520 as it is a cat-back system that does not alter the catalytic converter location or O2 sensor positioning. However, a professional tune is recommended to optimize air-fuel ratios and realize any performance gains from the improved exhaust flow.

Q: Will the quad carbon fiber tips on the 11514520 line up with my Mustang GT rear fascia openings?
A: Yes. Kooks designs the 11514520 tip position and angle to align with the factory dual rear fascia exhaust openings on the 2018 through 2024 Mustang GT S550. Proper alignment is achieved during installation before final tightening of all clamps and hangers.

Q: How long is the lead time for the Kooks 11514520?
A: Each 11514520 is built to order at Kooks' USA manufacturing facility. Standard lead time is 4 to 6 weeks from order confirmation. Orders placed during high-demand periods may extend to 8 weeks. Contact us before ordering if you have a specific event or delivery deadline.

Q: What is the warranty on the Kooks 11514520 valved cat-back?
A: Kooks provides a limited lifetime warranty on all stainless steel components of the 11514520 to the original purchaser. The valve actuators and electronic components are covered under a separate limited warranty. review the full Kooks warranty documentation included with your order for complete terms and conditions.

Q: Is the Kooks 11514520 louder than the stock Mustang GT exhaust?
A: Yes. With the valves open, the 11514520 delivers a noticeably louder and more aggressive tone than the factory cat-back. With the valves closed, the system produces a sound level comparable to a mildly upgraded factory exhaust, making it practical for daily use without excessive drone or cabin noise at highway speeds.

Q: Can I use the Kooks 11514520 with aftermarket long tube headers on my S550 Mustang GT?
A: Yes. The 11514520 is a cat-back system that connects at the OEM mid-pipe outlet, so it is compatible with any long tube or short tube header setup that retains a standard OEM-diameter mid-pipe outlet. If you install aftermarket long tube headers and an aftermarket mid-pipe or X-pipe, confirm the outlet diameter matches the 11514520 inlet before ordering.

Prop 65 Warning

California Proposition 65 Warning: This product can expose you to chemicals including Chromium and Nickel, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

Installation Instructions

1. Raise the vehicle on a lift or secure jack stands and allow the factory exhaust system to cool completely before beginning removal.
2. Disconnect the negative battery terminal before working near any exhaust valve wiring or electronic components.
3. Remove the factory cat-back exhaust by unbolting the OEM mid-pipe-to-catback connection flange and unclipping all rubber exhaust hangers. Slide the factory system rearward and out of the vehicle.
4. Inspect the OEM mid-pipe outlet flange for damage, corrosion, or warping. Clean the mating surface before installing new gaskets or clamps.
5. Begin assembly of the Kooks 11514520 system starting with the H-pipe section. Loosely connect the H-pipe to the OEM mid-pipe outlets and engage all hangers without fully tightening to allow final alignment.
6. Connect the 3 inch mid pipes to the H-pipe outlets and route them toward the rear of the vehicle, engaging all hangers and checking for clearance around the driveshaft, fuel tank, and suspension components.
7. Attach the shotgun valved muffler sections to the mid pipes and route the 3 inch rear pipes through the rear valance openings. Align the quad carbon fiber tips with the factory rear fascia cutouts before tightening any connections.
8. With all components positioned and aligned, tighten all clamps and fasteners evenly from front to rear. Verify adequate clearance between all exhaust pipes and the undercarriage, fuel lines, and brake lines.
9. Route and connect the valve actuator wiring harness following the Kooks installation manual. Connect to the valve control module and mount the controller in a convenient in-cabin location according to the instructions provided.
10. Reconnect the negative battery terminal, start the engine, and cycle through both valve positions to confirm valve operation and inspect all connections for exhaust leaks with the engine at operating temperature.