Pipes, Flanges and Downpipes

Missing a section of pipe, a bend or a flange to make your exhaust fit? In this category we bring together pipes, bends, flanges, downpipes, flex pipes and adapters for you who build or repair an exhaust yourself or adapt an existing system to a new project.

What each part does

Straight pipes and exhaust tubing in lengths form the actual pipe routing, while exhaust bends guide it around the underbody, axle and tank. Flanges and adapters join parts with different diameters or connection types, and a flex pipe absorbs engine movement so joints and hangers are typically put under less stress. Turndown tailpipes direct the gas down under the car. Downpipes connect the turbo to the rest of the exhaust; the range includes, for example, downpipes from Diamond Eye Performance with a direct turbo flange and V-band clamp. Other brands in the category include Magnaflow, Stainless Bros, Stainless Works and Remus.

How to choose pipes, flanges and downpipes

• Diameter: The pipe diameter should suit the engine's power and the rest of the system. A bigger pipe is not automatically better – it depends on the project and can change both sound and gas flow.
• Material: Stainless steel typically resists corrosion better, while mild or coated steel can be easier to work with. Some downpipes are available in several material versions.
• Connection type: Flanges, V-bands and clamps must match each other and the space you have for installation.
• Fitment: Downpipes and connecting pipes are often made for specific engines or turbo types, so check the part number against your car.

Installation, inspection and maintenance

Measure and test-fit before you weld or do the final tightening, and use new gaskets on flange joints. A flex pipe should not be used to correct misaligned pipes, as this can wear the braiding. Pipes close to fuel lines or brake lines may need a heat shield. Whether the modification can be approved for roadworthiness inspection depends on the product and the car – this applies especially to downpipes without a catalytic converter – so check the E-mark and requirements for the specific part number. Re-tighten the joints after the first few drives and keep an eye out for leaks at the flanges.

Frequently asked questions

What is the difference between a downpipe with and without a catalytic converter?

A downpipe with a catalytic converter cleans the exhaust gas, while one without typically gives less back pressure but often cannot be approved for road use. Whether a specific downpipe can pass inspection depends on the product and the car, so check the part number.

Where should the flex pipe be placed in the exhaust?

The flex pipe is typically placed close to the engine or turbo, where movement is greatest. The exact position depends on the system, and the pipe must be installed straight and without twisting to last.

Can I join pipes with different diameters?

Yes, with an adapter or a reducer you can join pipes of different sizes. Measure both the inside and outside diameter so the transition fits tightly, and choose a connection type that suits the rest of the system.