The Helix Downpipe is the optimal downpipe for the performance minded Suby owner. This downpipe features a cast bellmouth which provides the absolute maximum exhaust flow and minimum back pressure by allowing the wastegate gases to exit without disrupting normal exhaust flow. The piping is full 3" Stainless Steel (304) polished, and the package includes gaskets & bolts. This downpipe replaces both cats and is designed for USDM fitment only. The combination of the Helix uppipe, downpipe, and exhaust system will yield 30+whp!