Unleash Your Engine's Power with 3 Inch High Flow Catalytic Converters

An Introduction to 3 Inch High Flow Catalytic Converters

For car enthusiasts looking to increase the performance and power output of their vehicles, installing aftermarket high flow catalytic converters is a popular modification. High flow catalytic converters maximize exhaust flow for boosted engine efficiency while still controlling emissions. Upgrading to a larger 3 inch inlet/outlet catalytic converter is ideal for modified engines with increased displacement and airflow.

In this comprehensive guide, we'll discuss what high flow cats are, the benefits of 3 inch catalytic converters, how to choose the right one for your vehicle, installation tips, and frequently paired performance upgrades to consider.

What Are High Flow Catalytic Converters?

Catalytic converters are emissions control devices installed on all modern vehicles in the exhaust system between the engine and muffler. They convert toxic exhaust gases like hydrocarbons, carbon monoxide and nitrogen oxides into less harmful compounds like nitrogen, carbon dioxide and water vapor.

High flow catalytic converters increase exhaust flow and reduce backpressure compared to stock catalytic converters. They feature larger diameter tubing, less dense substrate material and increased internal volume for maximized airflow. The improved exhaust flow enhances engine efficiency and horsepower output.

Benefits of 3 Inch High Flow Converters

Three inch diameter high flow converters provide significant exhaust flow improvements over smaller stock or aftermarket catalytic converters. Benefits of upgrading to a 3 inch high flow catalytic converter include:

• Increased peak horsepower and torque output
• Better throttle response and acceleration
• Higher top-end speed
• Improved engine efficiency
• Reduced exhaust backpressure
• Cleaner exhaust emissions
• Aggressive exhaust tone

With their large internal volume, 3 inch catalytic converters can meet the airflow demands of highly modified engines. They prevent exhaust restrictions that sap power. The reduced backpressure and improved cylinder scavenging provides noticeable horsepower and torque gains throughout the RPM band.

Choosing the Right 3 Inch High Flow Converter

Picking the optimal 3 inch catalytic converter depends on your vehicle's engine size, power modifications, and emissions regulations in your area. Consider these factors when choosing a high flow cat:

• Vehicle Make/Model/Engine - Match the inlet and outlet size to your existing exhaust.
• Fuel Type - Opt for a converter compatible with gasoline or diesel exhaust.
• Engine Displacement - Larger engines require greater flow capacity.
• Power Modifications - More modified engines need higher volume cats.
• Emissions Laws - Choose CARB-approved cats for California vehicles.
• Material - Metallic substrate lasts longer than ceramic.

Select a catalytic converter that will provide minimal exhaust restriction while effectively treating emissions. Never install a test pipe in place of a catalytic converter as this is illegal.

Typical 3 Inch Converter Installations

Some common vehicles and engine swaps that benefit from upgrading to a 3 inch high flow catalytic converter include:

• Nissan 350Z/370Z with 3.5L V6
• BMW 335i with 3.0L twin-turbo inline-6
• Ford Mustang GT with 5.0L Coyote V8
• Chevrolet Camaro SS with 6.2L LS3 V8
• Pontiac GTO with 6.0L LS2 V8
• Jeep Wrangler with 4.0L inline-6 or 5.7L HEMI V8
• Toyota Supra with 2JZ-GTE inline-6 swap
• Nissan 240SX with LS V8 swap

High horsepower turbocharged import cars, muscle cars, trucks, and engine swapped vehicles are ideal candidates for upgrading to a 3 inch catalytic converter.

Installing a 3 Inch High Flow Catalytic Converter

Replacing your stock catalytic converter with a larger 3 inch high flow converter is a relatively straightforward bolt-on upgrade. Here is a general overview of the installation process:

Step 1 - Secure the Vehicle

Lift your vehicle onto jack stands or drive it over a lift to access the underside. Use the factory jacking points and ensure the vehicle is stable before working underneath.

Step 2 - Locate the Converter

Find the catalytic converter mounted midway along the exhaust system. It is usually connected to the manifold downpipe and midpipe with flanges.

Step 3 - Disconnect Sensors

Unplug the upstream oxygen sensor if equipped. Also disconnect any heat shields from the converter body.

Step 4 - Loosen Clamps and Bolts

Loosen the flange nuts/bolts and any exhaust clamps connecting the stock catalytic converter. Spray them with penetrating oil if seized.

Step 5 - Remove Old Converter

Once detached, carefully remove the stock catalytic converter from the exhaust system. Maneuver it off the hanging exhaust pipes.

Step 6 - Install New Converter

Position the new high flow converter in place with the directional arrow pointing forward. Line up the 3 inch inlet and outlet. Reinstall the flanges or clamps.

Step 7 - Tighten Connections

Evenly tighten the flange nuts/bolts and clamps to secure the new 3 inch cat. Torque them to the manufacturer's specifications.

Step 8 - Reconnect Sensors

Plug the upstream O2 sensor back in. Reattach any heat shields onto the catalytic converter body.

Step 9 - Lower Vehicle

Raise the vehicle off the jack stands/lift and perform a final inspection before starting the engine.

Road test your car to feel the power gains and verify there are no exhaust leaks. Your 3 inch high flow converter is now ready to reduce backpressure and enhance performance!

Pairing Performance Upgrades with 3 Inch Cats

To maximize the benefits, consider complementing your new 3 inch catalytic converter with these other bolt-on modifications:

Aftermarket Exhaust System

Installing a complete mandrel bent exhaust system with 3 inch pipes pairs perfectly with a larger high flow converter. It reduces turbulence and maintains optimal exhaust velocity.

Tuner Chip/programmer

An ECU tuner chip recalibrates the air/fuel ratio, timing, rev limit, and other parameters to match the increased airflow from bigger 3 inch exhaust components.

Cold Air Intake

Forced induction cold air intakes feed cooler, denser outside air to the engine for more power. Match this with free-flowing exhaust.

Headers/Downpipe

Upgrade to performance exhaust manifolds or header assemblies leading into the catalytic converter for further exhaust enhancements.

With supporting mods like these, your 3 inch high flow catalytic converter will unleash the full performance potential of your engine.

Frequently Asked Questions

Can you run without a catalytic converter?

No, removing your catalytic converter entirely is illegal, will set a check engine light, and can fail emissions testing. Always keep a functioning catalytic converter installed.

Do 3 inch catalytic converters add horsepower?

Yes, by reducing exhaust backpressure, a 3 inch high flow catalytic converter can increase peak horsepower and torque output across the engine's RPM range compared to smaller converters.

Is it worth upgrading catalytic converter?

On modified, high performance vehicles, upgrading to a larger high flow catalytic converter is worth it for the power gains, smoother exhaust flow and aggressive sound.

Should I get a catless or catted downpipe?

Always go with a catted downpipe that includes a high-flow catalytic converter. Catless downpipes are not street legal and cause excess emissions.

How often do catalytic converters need to be replaced?

Factory catalytic converters usually last 8-12 years or 80,000-100,000 miles before needing replacement. Quality high flow converters can last over 15 years with proper maintenance.

Let the Power of 3 Inch Cats Revitalize Your Ride

Installing a 3 inch high flow catalytic converter is an impactful bolt-on upgrade for boosted power gains, throttle response and exciting exhaust sound. Match your larger converter with supporting intake, header and exhaust mods to fully unleash your engine's performance. With the right high flow cat, you'll be flying down the straightway in no time!

FAQs

Do you need a tune with a catalytic converter?

It's recommended to get an ECU tune to optimize your air/fuel ratios and engine parameters when upgrading to a high flow catalytic converter. This allows your engine computer to adapt to the increased airflow.

What are the symptoms of a clogged catalytic converter?

Signs of a restricted catalytic converter are lack of power, poor acceleration, reduced fuel economy, smelly exhaust, glowing converter and triggering of check engine light trouble codes.

Do catless pipes smell bad?

Yes, removing your catalytic converter and installing straight pipes or test pipes will produce an obnoxious exhaust odor along with smelly fumes inside the cabin when windows are down.

Can I pass emissions with a catless downpipe?

No, removing the catalytic converter from your downpipe or exhaust manifold will cause immediate emissions test failure. Always keep the cat intact.

How much power gain from high flow cat?

Typical horsepower gains from installing a 3 inch high flow catalytic converter are in the 10-25 HP range depending on the engine and supporting mods. Performance improves across the RPM range.