Flanges join two sections of exhaust pipe or connect a header collector to the rest of the system, using bolts to clamp a gasket between two flat faces. The most common patterns are 2 bolt flanges and 3 bolt flanges, along with specialised turbo base plate flanges for turbo housing connections. Getting the bolt pattern right is essential — count the bolt holes and measure the spacing on your existing flange, or match it to your header or manifold before ordering.

How do I know what bolt pattern flange I need?

Measure the bolt hole spacing and count on your existing flange, or match it to your header or manifold's pattern — most commonly 2, 3 or 4 bolt.

What's the difference between mild steel and stainless flanges?

Stainless resists corrosion and lasts significantly longer, especially in coastal areas, while mild steel is a cheaper option that will rust over time without regular care.

Do flanges come with matching gaskets?

Not usually — flanges and gaskets are sold separately, so pair your flange with a gasket cut for the same bolt pattern and pipe diameter for a proper seal.

Can I weld a flange to any size pipe?

Yes, flanges are sized by pipe diameter, so choose the flange that matches your exhaust tube's outside diameter before welding it into place.