Milltek Sport Large-Bore Downpipes are designed to enhance both performance and sound. These downpipes feature a larger diameter compared to standard OEM parts, allowing more exhaust gas to exit the engine and pass through, which increases efficiency. When used with the Catalyst Bypass Pipe, significant power gains can be achieved without restriction from a catalyst. All Milltek Sport performance exhaust systems are manufactured in the UK and distributed to over 90 countries worldwide. Warning: This product is intended for motorsport use only and requires a Stage 2 ECU remap. - Larger diameter than OEM for improved gas flow - Designed for increased efficiency and performance - Compatible with Catalyst Bypass Pipe for significant power gains - Manufactured in the UK and distributed globally Specifications: - Pipe Diameter: 76.20 - Race Product: Yes - EMarked: No Kit comes with: - MSBM266: LH Primary Cat Rep Downpipe - MSBM266 - MSBM267: RH Primary Cat Rep Downpipe - MSBM267 - MSBM268REP: Secondary Cat Bypass - MSBM268REP Vehicle Compatibility: - 2014-2018 BMW 3 Series F80 M3 & M3 Competition Saloon (Non OPF/GPF Models Only) - 2014-2018 BMW 4 Series F82/83 M4 Coupe/Convertible & M4 Competition Coupe (Non-OPF equipped models only)