Fi Exhaust Downpipe for BMW G20/G21 M340i B58

Catless Standard Version

The ultra-high flow catless downpipes remove restrictive factory catalytic convertor. They increase exhaust gas flow and performance gains, produce higher sound volume. And is usually recommended option going further with ECU tuning.

Race 100Cell

This kind of catalyst is generally used in race cars , so it is often called “racing catalyst”. With the larger cells and fast exhaust flow rate, it is smooth, durable and do not have refractory wool burn-out problems. The higher the number of the cells, the smaller and denser the hole is. The higher the back pressure, the more it can enhance torque performance, while the opposite is true for increasing horsepower.Converting your stock catalyst converter (400~800 CPSI) into our metallic catalyst converters will result in significant enhancements in airflow discharge that circumvents the limitations and parameters set by car manufacturers.

Sport 200Cell

With the larger cells and fast exhaust flow rate, it is smooth, durable and do not have refractory wool burn-out problems. The higher the number of the cells, the smaller and denser the hole is. The higher the back pressure, the more it can enhance torque performance, while the opposite is true for increasing horsepower.Converting your stock catalyst converter (400~800 CPSI) into our metallic catalyst converters will result in significant enhancements in airflow discharge that circumvents the limitations and parameters set by car manufacturers.