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300 Cell Catalytic Converters

Premium 300 CPSI Metallic Core Converters for Street & Custom Builds

Find the perfect balance between engine performance and emission control with our 300 cell high flow catalytic converters. While 100 and 200 cell units are designed for maximum race flow, the 300 CPSI (cells per square inch) configuration is widely considered the ideal upgrade for street-driven performance vehicles. These converters significantly reduce backpressure compared to restrictive OEM parts, allowing your engine to breathe easier and produce more power without the excessive exhaust smell or "raspy" tone often associated with lower cell counts. Shop our selection of high-quality metallic core cats and experience smoother acceleration and a deeper exhaust note.

Exhaust Shop Australia stocks specialized 300 cell universal converters from trusted Australian brands like MSA and Redback. Unlike ceramic factory converters that can crack under extreme heat or vibration, our 300 cell range uses a rugged metallic substrate, making them ideal for high-performance applications.

Technical Specifications:

  • Inlet/Outlet Sizes: Available in 2" (51mm), 2.25" (57mm), and 2.5" (63.5mm) diameters to suit a wide range of standard and performance exhaust systems.
  • Substrate: High-flow Metallic Core for superior heat dissipation and structural integrity.
  • Body Construction: Durable 409 Stainless Steel bodies, designed to resist corrosion in harsh Australian environments.
  • Compliance: Rated to Euro 2 standards, these units are excellent for older performance vehicles looking to maintain environmental responsibility while gaining power.

We offer fast, insured shipping Australia-wide, reaching customers in Melbourne, Sydney, Brisbane, Perth, Adelaide, and Hobart daily. Our central logistics network ensures that whether you’re in a metro workshop or a regional garage, your fabrication parts arrive ready for your next project.

Frequently Asked Questions

Why choose a 300 cell converter over a 200 cell unit?

A 300 cell converter provides slightly more surface area for the chemical catalyst reaction to occur. This often makes it more effective at preventing "Check Engine" lights (CEL) on modern ECU systems and reduces the raw fuel smell (exhaust fumes) better than a 200 cell unit, while still flowing much better than a standard factory cat.

Is a metallic core better than a ceramic core?

Yes, for performance use. Metallic substrates are much thinner than ceramic walls, allowing for more open space and better airflow. They are also significantly more durable and can withstand the higher temperatures and vibrations found in modified or turbocharged engines.

Are these 300 cell converters legal for road use?

In Australia, any aftermarket converter must technically meet or exceed the emission standards of the vehicle's original equipment. These 300 cell units are designed to provide high-flow performance while helping vehicles meet Euro 2 requirements. Always check your local state's specific registration and engineering requirements.

Do I need to weld these in?

Most of the 300 cell converters in our collection are universal fitment, meaning they have a "barrel" shape and require professional welding to be integrated into your exhaust piping. This ensures a leak-free, custom fit for any vehicle make or model.