ApexBuilt® BMW F97 X3M & F98 X4M Resonated Mini-Cat Downpipes (S58, 2020+)

NO TUNE REQUIRED! Our unique O2 sensor housing design allows for a direct bolt-on installation, without resulting in a check engine light – even on otherwise fully stock cars.  ApexBuilt® BMW F97 X3M & F98 X4M Resonated Mini-Cat Downpipes offer... • Perfect fitment, guaranteed.  • No check engine light, no error codes. No need to unlock your DME, no tune required.  • Drastically improved throttle response, quicker turbo spool, and an aggressive exhaust note. • Estimated gains of 20-25+ wheel horsepower and 40-50+ TQ when installed on a vehicle that is not tuned. • Estimated gains of 60+ HP and 100+ TQ over stock power levels when paired with an aftermarket ECU tune. • T304 stainless steel construction  • Lifetime warranty    PLEASE NOTE: These these parts are for OFF ROAD / RACE USE ONLY . They are not 50 state legal. Any of our catless race downpipes WILL NOT be sold in, or shipped to, the state of California. We advise you to run a tune on your vehicle for best results.