How a Borla Cat-Back Exhaust Changes Your Car

Upgrading your vehicle’s exhaust system is one of the most effective ways to improve performance, sound, and driving enjoyment. Borla Performance Industries has built a reputation for producing high-quality stainless steel exhaust systems that deliver a distinct aggressive tone and measurable power gains. A cat-back exhaust replaces the piping from the catalytic converter back to the tailpipe, removing restrictive factory components. This article covers the real-world benefits, sound profiles, expected power increases, and a detailed installation guide to help you decide if a Borla cat-back is the right modification for your car.

Benefits of a Borla Cat-Back Exhaust

A Borla cat-back system is more than a simple upgrade. It brings together engineering, material quality, and tuning expertise to offer a range of advantages over the stock exhaust.

Improved Performance and Airflow

Factory exhaust systems are often designed for noise reduction and cost savings, not maximum flow. Borla uses mandrel-bent tubing to maintain a consistent inside diameter, which reduces backpressure and allows exhaust gases to exit more freely. This improved scavenging effect helps the engine breathe better, especially at higher RPMs. The result is a noticeable increase in horsepower and torque, particularly in the mid-to-upper powerband. Many users report gains between 10 and 15 horsepower on naturally aspirated engines, and even more on forced-induction setups when combined with other modifications.

Distinctive Sound Tuning

Borla exhausts are famous for their aggressive, refined sound. The company’s patented Aero-Turbine technology uses a tuned resonance chamber that cancels out unwanted frequencies while amplifying the desirable ones. This gives the exhaust a deep, rich tone at idle that turns into a snarling growl under throttle. Unlike some aftermarket systems, Borla designs its mufflers and resonators to minimize interior drone at highway speeds, keeping daily driving comfortable.

High-Quality Construction and Durability

All Borla cat-back systems are made from 304 stainless steel, which offers superior corrosion resistance compared to aluminized steel or mild steel. The tubing, mufflers, and tips are TIG-welded for strength and a clean appearance. Borla backs its products with a limited million-mile warranty, reflecting confidence in the materials and manufacturing. The hardware (clamps, bolts, hangers) is chosen to survive years of heat, moisture, and road salt.

Direct Fit and Bolt-On Installation

Most Borla cat-back systems are designed as bolt-on replacements. They include pre-formed pipes, clamps, and isolation mounts that match the factory mounting points. No cutting, welding, or special fabrication is required for most modern vehicles. The system typically uses band clamps or lap-joint clamps that seal tightly and allow for adjustment. This makes installation accessible to DIY enthusiasts with basic hand tools and a willingness to work under the car.

Sound Characteristics by Borla Series

Borla offers several exhaust series, each with a specific sound profile. Choosing the right series depends on your preference for volume, tone, and how much drone you can tolerate.

Borla Touring (formerly Pro XS)

The Touring series is the mildest of the Borla cat-back options. It produces a deep, smooth tone that is noticeably louder than stock but not overbearing. It is ideal for daily drivers who want a sporty sound without excessive cabin noise. The Touring series often uses a larger muffler body and additional resonators to keep the volume controlled while still improving flow.

Borla S-Type

The S-Type (Sport) exhaust is the most popular choice. It strikes a balance between aggressive sound and comfort. At idle, the tone is deep and muscular. Under hard acceleration, it opens up with a sharp, aggressive growl that turns heads. Drone is minimal inside the cabin at cruising speeds, though slightly more present than the Touring series. The S-Type is often recommended for those who want a noticeable upgrade without going overboard.

Borla ATAK

ATAK stands for “Acoustically-Tuned Applied Kinetics.” This is the loudest and most aggressive series Borla makes. It uses a straight-through muffler design with minimal sound deadening, delivering maximum volume and a raw, track-inspired exhaust note. The ATAK system has a pronounced crackle and pop on deceleration. It is ideal for weekend track cars or owners who want the loudest legal exhaust. Cabin drone is more noticeable, especially in the 1500–2500 RPM range, so it is less suited for long highway trips.

Sound Variability by Vehicle

The same Borla system can sound different on a V8 versus a V6 or a four-cylinder engine. Exhaust pulses, engine displacement, and header design all influence the final tone. For example, a Borla S-Type on a Chevrolet Camaro SS will have a deep, rumbling bark, while the same system on a Honda Civic Si will produce a sharper, more raspy note. Always listen to sound clips specific to your vehicle before purchasing.

Expected Power Gains with a Borla Cat-Back

Power gains are one of the primary reasons to upgrade, but they are often overestimated by first-time buyers. A cat-back exhaust alone typically adds 5–15 horsepower and 8–12 lb-ft of torque on a modern car. The exact improvement depends on how restrictive the factory exhaust was and the engine’s tuning.

Dyno-Proven Increases

Independent dyno tests for popular applications show consistent gains. A 2015 Mustang GT with a Borla ATAK cat-back gained 12 horsepower and 10 lb-ft of torque at the wheels. A 2018 Ram 1500 with the 5.7L HEMI saw a 10-horsepower increase and a noticeable improvement in throttle response. Turbocharged cars like the Subaru WRX often see smaller peak gains (6–8 horsepower) but a broader torque curve because the turbo creates its own backpressure. The benefit is less on highly boosted engines where the stock exhaust is already free-flowing, but the sound improvement remains compelling.

Torque Curve and Throttle Response

Beyond peak numbers, a Borla cat-back improves the torque curve. Reduced backpressure allows the engine to rev more freely, which feels like stronger acceleration from 2,500 RPM up. Throttle response sharpens because the engine does not have to fight against a restrictive exhaust. This is especially noticeable on manual transmission cars where rev-matching becomes easier and more satisfying.

Real-World Driving Impressions

Most owners report that the car feels quicker even if the dyno numbers are moderate. The combination of improved sound and slightly better acceleration creates a more engaging driving experience. For maximum power, pair the cat-back with a cold air intake and a performance tune. Many Borla systems are designed to work with aftermarket headers and downpipes, but a tune may be required to avoid check engine lights if the catalytic converters are removed.

Installation Tips for a Borla Cat-Back Exhaust

Installing a Borla cat-back is a manageable DIY project that typically takes 2–4 hours. The exact time depends on the condition of the factory hardware and your experience. Follow these steps for a clean, leak-free installation.

Tools and Materials Needed

  • Socket set (metric and SAE depending on vehicle)
  • Wrenches (combination and line wrenches)
  • Breaker bar or ratchet with long handle
  • Penetrating oil (ex: WD-40 Specialist or PB Blaster)
  • Floor jack and jack stands (or ramps)
  • Safety glasses and gloves
  • Exhaust hanger removal tool (or large pliers and lubricant)
  • Torque wrench (for final tightening)
  • Optional: angle grinder with cutting wheel (if bolts are seized)

Step 1: Prepare the Vehicle

Park on a level surface and let the exhaust cool completely. Hot pipes can burn you and cause bolts to swell, making removal harder. Disconnect the battery’s negative terminal to prevent accidental short circuits, though it is not always necessary. Raise the rear of the car using a jack and secure it with jack stands. Ensure the car is stable before crawling underneath.

Step 2: Remove the Old Exhaust

Spray penetrating oil on all exhaust hanger mounts and flange bolts. Allow it to soak for 10–15 minutes. Start at the rear and work forward. Unbolt the axle-back or cat-back sections at the slip joints or flanges. Use a hanger removal tool or lubricated pliers to slide the rubber hangers off the mounting studs. If any bolts are rusted and refuse to turn, use a torch (carefully) or cut the bolt with a grinder. Do not force a seized bolt, as it can break off inside the flange. On older vehicles, the mid-pipe may need to be cut if the factory system is one piece. A reciprocating saw with a metal-cutting blade works well.

Step 3: Dry-Fit the Borla System

Before tightening anything, position all Borla components loosely under the car. Start from the front (cat-back section that connects to the catalytic converter) and work back. Install the hangers into the rubber isolators. Do not tighten the clamps yet. Adjust the muffler and tailpipes for clearance around the rear axle, bumper, and heat shields. Ensure the tips are centered in the cutouts. Many Borla systems have adjustable tailpipe sections to fine-tune the tip position.

Step 4: Tighten All Connections

Once everything is aligned, begin tightening the clamps and bolts. Follow the sequence recommended in the Borla manual (usually front to back). Use a torque wrench to avoid overtightening and damaging the flanges or clamps. Borla band clamps require a specific torque—too much can distort the pipe, too little causes leaks. Most clamps are tightened to 30–40 ft-lb, but check your specific instructions. Re-tighten after 100 miles as the system settles.

Step 5: Check for Leaks and Clearance

Start the engine and let it idle. Listen for hissing sounds or popping at the joints, which indicate exhaust leaks. Have a helper rev the engine while you inspect connections. Use a soapy water spray bottle on the joints; bubbles indicate leaks that need further tightening. Also check that no part of the exhaust contacts the underbody, driveshaft, or suspension. Contact can cause annoying rattles or damage. If clearance is tight, loosen the clamps and reposition the pipe.

Common Installation Mistakes

  • Not using penetrating oil – Rusted bolts will snap or strip. Always soak before attempting removal.
  • Forgetting to reinstall O2 sensors – Some vehicles have sensors near the cat-back connection. If you unplugged them, plug them back in before starting the car.
  • Overtightening band clamps – This can deform the pipe and create a poor seal. Follow torque specs.
  • Skipping the dry-fit step – Tightening everything too early often leads to misaligned tips and rattling. Always adjust first.

Tips for Older Vehicles

If your car is more than 10 years old, exhaust bolts and hangers may be heavily corroded. Have a replacement hanger kit on hand. Use anti-seize compound on all new bolts and slip joints to make future removal easier. If the catalytic converter flange bolts are rusted, consider replacing them with stainless steel hardware. An exhaust shop can weld new flanges if the old ones are too damaged.

Borla cat-back systems are legal for street use in all 50 states because they do not remove or alter the catalytic converters. They are classified as “cat-back” systems, which means they replace only the piping behind the factory catalyst. No check engine light should appear if the system is installed correctly. Borla’s million-mile warranty covers defects in material and workmanship but does not cover damage from improper installation, abuse, or off-road use. Keep your original exhaust parts in case you need to revert for emissions testing or dealership visits. Some dealers may void a warranty claim if an aftermarket exhaust is suspected of causing a problem, but this is rare when the system is properly installed and the vehicle is stock otherwise.

Conclusion

A Borla cat-back exhaust is a rewarding upgrade that transforms both the sound and driving character of your vehicle. Whether you choose the subtle Touring series, the balanced S-Type, or the aggressive ATAK, you will benefit from improved airflow, higher-quality materials, and a noise that makes every trip more exciting. Installation is straightforward with the right tools and preparation, and the power gains—while modest—are noticeable in everyday driving. To get started, browse the specific system for your car on the Borla official website or consult vehicle-specific forums like Camaro6 and Mustang6G for owner reviews and sound clips. A Borla cat-back is an investment in driving pleasure that will last for the life of your car.