Audi R8 (Gen2) Facelift - OPF Spare Pipes - ONLY for EU Market OPF CarsThe new R8 now includes OPF (Otto Particle Filters) after the cats. OPF Spare Pipes (delete) are available here (will require a tune for CEL removal). These lightweight test pipes fit in place of the heavy OPF Filters on the new R8 (2020+). Using test pipes removes the flow restriction a the filters places on an exhaust system, while increasing the horsepower. The silencing effect of the filters are also removed, enhancing the aggressive engine sound.