4.5" Downpipe for BMW B58 Gen 1

The Evolution Racewerks 4.5″ Downpipe is engineered to unleash greater performance from BMW's B58 Gen 1 engines found in F chassis models. By replacing the restrictive factory catalytic converter, this high-flow, competition-grade component significantly boosts horsepower and torque, improves throttle response, and allows for faster turbo spool-up times. Its construction features 100% stainless steel piping, precision TIG welding for durability, and a CNC-machined V-band flange for a secure connection. The downpipe is available in a standard brushed finish, with optional polished or high-temperature black thermal coatings to reduce underhood temperatures and enhance corrosion resistance. It also includes options for an additional O2 sensor bung for wideband monitoring and an EGT sensor bung for temperature gauges, both supplied with pre-installed plugs. The design incorporates a 100% stainless steel flex section, mirroring BMW's approach to reduce stress on exhaust components, turbochargers, and exhaust manifolds, thereby preventing premature wear and tear and potential stress failures. Installation is rated as a 3 out of 5 in difficulty. It is crucial to note that this product is intended for OFF ROAD COMPETITION USE ONLY and is not legal for use on pollution-controlled vehicles on public roads or highways. It is for sale for all 49 states excluding California, and requires a Vehicle Compliance Waiver. This item is strictly NOT FOR SALE, INSTALLATION, OR USE on licensed vehicles in the state of California. International customers may purchase without restriction. The downpipe is compatible with both factory and aftermarket exhaust systems and includes all necessary hardware for a complete installation.