APEXBUILT® BMW G87 M2, G80 M3, & G82/G83 M4 GESI HIGH-FLOW CATTED DOWNPIPES (S58, 2021+)

*FROM APEX BUILT* ApexBuilt® G8X M2/M3/M4 GESI HFC Downpipes offer... • No check engine light on factory-tuned vehicles. • 49 state emissions legal* • Industry-leading build quality. • Perfect fitment, guaranteed. • Drastically improved throttle response, quicker turbo spool, and an aggressive exhaust note versus OEM. • Estimated gains of 20-25+ wheel horsepower and 40-50+ TQ when installed on a vehicle that is not tuned. • Estimated gains of 45+ HP and 60+ TQ over stock power levels when paired with an aftermarket ECU tune. • TIG-welded T304 stainless steel construction, assembled by hand in Naples FL. • EPA approved GESI GEN2 UHO metal-core 400cpsi 4.5" cats, rated for 500-800hp applications & road legal in 49 states.  • Lifetime warranty. *PLEASE NOTE: These downpipes will not be sold or shipped to the state of California. GESI 400cpsi cats are EPA approved, but not CARB approved – meaning they're street legal in all 49 states EXCEPT the state of California.  Read more about GE