Milltek Secondary Catalyst Bypass is a direct-fit performance component engineered to optimize exhaust flow on the Porsche Cayenne 958 Turbo 4.8 V8 (pre-facelift).
CNC-formed T304L stainless steel construction with hand-finished welds. Engineered to work seamlessly with OEM mounting points and Milltek Cat-Back systems, preserving OEM+ fitment integrity while maximizing scavenging efficiency across the rev range.
Pre-facelift vs facelift, explained: This part is built for the pre-facelift Cayenne 958, known as the 958.1, sold from launch through the 2014 model year. Porsche facelifted the Cayenne in mid-2014, creating the 958.2 for the 2015 to 2018 model years, with revised headlights, a new front bumper and a restyled tailgate. Because the 2014 model year straddles the changeover, confirm your car is a pre-facelift 958.1 before ordering. Milltek does not offer a facelift 958.2 version of this part.