Audi RS6/RS7 C8 & S8 D5 - Large Bore DownpipesMilltek Sport Large Bore Downpipes are perfect when looking to improve both performance and sound. These downpipes are fabricated with a larger diameter than standard OEM parts, meaning that there is significantly more space for more gas to exit the engine and pass through, increasing efficiency. Used with our Catalyst Bypass Pipe, you can expect significant power gain without any restriction on gas flow made by a catalyst. Our range of Cast Downpipes