3 Bolt Exhaust Flanges

Ensure a professional, leak-free finish for your custom exhaust project with our high-quality 3-bolt exhaust flanges. Designed specifically for Australian fabricators and automotive enthusiasts, these flange plates provide a robust and detachable connection point for headers, cat-back systems, and custom dump pipes. Available in a wide variety of diameters and thicknesses, our 3-bolt flanges are laser-cut for a precision fit, ensuring easy alignment and superior sealing when paired with our matching gaskets. Whether you are building a street-legal daily or a high-performance track car, shop our range of durable mild steel and stainless steel flanges with fast shipping nationwide.

What is the advantage of a 3-bolt flange over a 2-bolt design?

A 3-bolt flange provides more even clamping pressure around the exhaust gasket compared to a 2-bolt design. This significantly reduces the risk of exhaust leaks and "flange bowing," especially in high-heat areas like header collectors or near the catalytic converter.

Should I choose Mild Steel or Stainless Steel flanges?

If you are welding onto a standard mild steel exhaust system, a Mild Steel flange is easy to weld and cost-effective. However, if you have a stainless steel system or live in a coastal area where rust is a concern, 409 Stainless Steel is the better choice for its superior heat and corrosion resistance.

Do these flanges come with gaskets and bolts?

Generally, our 3-bolt flanges are sold as individual plates. To ensure a perfect seal, we recommend browsing our 3-Bolt Gaskets collection to find the matching size and bolt-hole pattern for your specific flange.

How do I measure a 3-bolt flange to ensure it fits?

The most important measurements are the Inside Diameter (ID), which should match the outside diameter of your exhaust tube, and the Bolt-to-Bolt Center distance. Most of our 3" flanges use an 85mm center-to-center measurement, but we provide detailed technical specs on each product page to ensure 100% compatibility.