Active Autowerke S58 BMW G8x M3/M4 DOWNPIPES Sport Cat

BMW introduced a new valvetronic, single turbo version of its direct-injection engine for the later F-Chassis models beginning in 2016 and continues into the G-Chassis models - the evolution to the S58 engine continues with the twin turbo variant used in the M-series vehicles. The Active Autowerke S58 downpipes for the X3M and X4M helps unleash some of the potential that is restricted by the OEM downpipes.

Turbochargers are powered by spent exhaust gases created during the combustion process. The quicker these gases are evacuated, the better. Unfortunately, the factory down pipe in the S58 is a bit restrictive, which results in slower exhaust gases and slower turbo spool.

The Active Autowerke X3M/X4M S58 Signature down pipe utilizes 3 inch diameter stainless steel piping in order to provide more power, quicker spool, and extreme durability. We've incorporated stainless flex joints and then down to 70mm to meet the OEM exhaust system. We never drop the diameter to smaller than the stock diameter of 70mm.

This variant includes a pair of 4.5" high flow GESI catalytic converters that will NOT produce a CEL!

The GESi G-Sport Ultra High Output Catalytic Converter features full 304 stainless steel construction, including the substrate. GESi UHO-Series Catalytic Converters are EPA registered and compliant in 49 states and fully OBD2 compliant, perfect for use on 1996 and newer vehicles. GESi proprietary precious metal loading technology ensures greatly reduced emissions, eliminating most "Check Engine Lights". These high flow catalytic converters outperform stock converters and provide a reliable solution to the most common catalytic converter problems.

The GESi UHO-Series Catalytic Converters are rated for engines putting out between 500 and 850 horsepower while maintaining a high flow capacity. The reduced back-pressure from this high flow catalytic converter will allow you to maximize your engines horsepower without the harmful emissions. Say goodbye to Check Engine Lights and failed emissions tests!