Installing an exhaust cutout is a popular modification among car enthusiasts seeking adjustable exhaust sound and performance. This device allows you to bypass part of your exhaust system, enabling you to switch between a quiet, stock-like exhaust tone and a louder, more aggressive sound with improved flow. Whether you want a stealthy daily driver or a roaring track machine, an exhaust cutout offers that flexibility.

This comprehensive guide will take you through the entire process of installing an exhaust cutout, from selecting the right kit to performing the installation, wiring the actuator, and ensuring safe operation and maintenance. With careful preparation and attention to detail, you can achieve a professional-quality installation that enhances both the sound and performance of your vehicle.

Understanding Exhaust Cutouts

Before diving into the installation, it’s important to understand what an exhaust cutout is and how it works. An exhaust cutout is essentially a valve installed on your exhaust pipe that can open or close a bypass path. When closed, exhaust gases flow through the muffler and catalytic converters as usual, maintaining stock sound levels and emissions. When opened, the exhaust gases bypass these components, resulting in reduced backpressure, increased flow, and a louder exhaust note.

Exhaust cutouts come in two main types:

  • Manual Cutouts: Operated by a lever or cable that you manually open or close.
  • Electric Cutouts: Equipped with an electric actuator controlled by a switch inside the cabin or a remote control.

Electric cutouts are more convenient and popular for modern vehicles, allowing instant toggling without needing to exit the car.

Benefits of Installing an Exhaust Cutout

  • Adjustable Sound: Easily switch between quiet and aggressive exhaust tones depending on your mood or environment.
  • Performance Gains: Opening the cutout reduces exhaust backpressure, potentially improving horsepower and throttle response.
  • Emissions Control: When closed, your vehicle operates within stock emissions parameters, which is important for street legality.
  • Versatility: Ideal for vehicles used both on streets and tracks, enabling compliance with noise rules while still enjoying performance benefits.

Tools and Materials Needed

Gathering all necessary tools and materials before starting will streamline your installation process. Here’s a detailed list:

  • Exhaust Cutout Kit: Ensure compatibility with your exhaust pipe diameter and vehicle application. Kits typically include the valve, actuator (if electric), clamps, gaskets, and wiring.
  • Socket Set and Wrenches: For loosening and tightening clamps and bolts.
  • Screwdrivers: Both flathead and Phillips for mounting brackets and electrical components.
  • Drill with Metal Drill Bits: Required if you need to drill mounting holes or access ports.
  • Gasket and High-Temperature Sealant: To ensure airtight, leak-free connections.
  • Exhaust Clamps or Welding Equipment: Clamps are easier for installation and future removal; welding provides a permanent, leak-proof bond.
  • Protective Gear: Safety glasses, gloves, and hearing protection.
  • Multimeter: Useful for testing electrical connections.
  • Jack and Jack Stands or Vehicle Ramps: To safely access the underside of your vehicle.
  • Heat-Resistant Tape and Cable Ties: For securing wiring away from hot exhaust components.

Preparation

Proper preparation ensures a smooth and safe installation process. Follow these steps to get ready:

  • Park on a Level Surface: Ensure the vehicle is parked on flat ground and the parking brake is engaged.
  • Cool Engine: Allow the exhaust system to cool completely to avoid burns.
  • Raise the Vehicle: Use a jack and jack stands or ramps to gain access to the exhaust system underneath.
  • Inspect Your Exhaust: Identify the section of pipe where the cutout will be installed. Typically, this is between the catalytic converter and muffler or just ahead of the muffler for easiest access.
  • Measure Pipe Diameter: Confirm your exhaust pipe diameter to ensure you purchase the correct cutout size.
  • Read Manufacturer Instructions: Familiarize yourself with the specific instructions provided with your exhaust cutout kit.

Step-by-Step Installation Guide

1. Removing the Existing Exhaust Section

Start by loosening the clamps or bolts securing the section of exhaust pipe where the cutout will be installed. Depending on your vehicle, you may need to remove a section of pipe entirely or cut the pipe to insert the cutout. Use the socket set or wrenches for bolts, and a reciprocating saw or pipe cutter for cutting.

Tips:

  • Mark the cut location with a marker or tape to ensure a straight cut.
  • Wear safety gloves and glasses when cutting metal.
  • If you plan to weld the cutout, leave enough pipe length for a secure weld.

2. Fitting the Exhaust Cutout

Position the cutout valve onto the exhaust pipe. Most kits come with clamps or flanges to secure the cutout in place.

Using Clamps: Slide the cutout over or between the cut pipe ends, apply a gasket if provided, and tighten the clamps securely to prevent leaks.

Using Welding: Tack weld the cutout in place, check alignment and valve operation, then complete the weld around the joints.

Important: Ensure the valve opens and closes freely without obstruction. The cutout’s actuator arm or lever should have enough clearance from the chassis or suspension components.

3. Installing the Actuator and Wiring (For Electric Cutouts)

If your cutout features an electric actuator, follow these steps:

  • Mount the Actuator: Secure the actuator onto the cutout valve using the provided brackets or hardware.
  • Route the Wiring: Run the wiring from the actuator to the vehicle’s interior, avoiding hot exhaust parts or moving suspension components.
  • Connect Power and Ground: Connect the actuator’s positive lead to a switched 12V power source (such as the ignition or fuse box) and the negative lead to a suitable ground point.
  • Install Control Switch: Mount the control switch in a convenient location inside the cabin. Connect the switch wiring according to the manufacturer’s wiring diagram.
  • Test Electrical Operation: Use a multimeter to verify proper voltage and continuity. Activate the switch to ensure the valve opens and closes smoothly.
  • Secure and Protect Wiring: Use cable ties and heat-resistant tape to secure wiring and protect it from heat damage.

4. Reassembly and Final Tightening

Once the cutout is securely mounted and wired, reassemble any exhaust components or heat shields that were removed during installation. Double-check all clamps and bolts are tightened to manufacturer torque specifications to avoid leaks or loosening during operation.

Final Checks and Testing

Before lowering your vehicle, perform the following checks:

  • Valve Operation: Activate the cutout switch or manually operate the valve to ensure it opens and closes completely without binding.
  • Leak Inspection: Start the engine and listen for exhaust leaks around the cutout. Tighten clamps or re-seal joints if necessary.
  • Clearance Check: Verify that the cutout and actuator do not contact suspension parts, brake lines, or the ground during normal driving.

After confirming all functions, lower the vehicle safely and take it for a test drive. Toggle the cutout valve at different RPMs and load conditions to experience the sound variation and ensure reliable operation.

Maintenance and Troubleshooting

To maximize the lifespan and effectiveness of your exhaust cutout, regular maintenance is essential:

  • Inspect for Corrosion: The exhaust environment is harsh, so periodically check the cutout and mounting hardware for rust or corrosion.
  • Lubricate Moving Parts: Apply high-temperature grease or lubricant to the valve shaft and actuator linkage to prevent sticking.
  • Check Electrical Connections: Ensure wires and connectors remain secure and free of corrosion or damage.
  • Clean Valve Interior: Carbon buildup can accumulate inside the valve, especially if frequently used. Clean with appropriate solvents during routine exhaust maintenance.

Troubleshooting Tips:

  • Valve Won’t Open or Close: Check actuator wiring and switch operation; physically inspect for obstructions or damage to the valve mechanism.
  • Exhaust Leaks: Tighten clamps or consider welding joints for a permanent seal.
  • Loud Rattling or Noise: Inspect for loose hardware or interference with other components.

While exhaust cutouts offer exciting performance and sound benefits, it is important to understand local laws and regulations regarding vehicle noise and emissions. Many jurisdictions prohibit tampering with emissions control devices or excessive noise levels on public roads. Always:

  • Use the cutout in compliance with local noise ordinances.
  • Keep the valve closed during street driving if required to meet emissions standards.
  • Consult your state or country’s vehicle modification laws before installation.

Using the cutout responsibly ensures you enjoy your modification without legal issues or environmental harm.

Conclusion

Installing an exhaust cutout is a rewarding modification that provides the best of both worlds: the ability to enjoy a quiet, comfortable ride or unleash an aggressive exhaust tone and improved performance at the push of a button. By carefully selecting the right kit, preparing adequately, and following step-by-step installation and wiring instructions, you can achieve a professional-level setup.

Remember, safety should always be your top priority. Wear protective gear, work in a well-ventilated area, and follow manufacturer guidelines closely. With proper installation and maintenance, your exhaust cutout will serve as a versatile and durable addition to your vehicle’s exhaust system.