Milltek Resonated Secondary Cat Bypass | BMW G8X M3 M4

Description

The Milltek Axle Back Resonated Secondary Cat Bypass is engineered for BMW G8X M3 and M4 models. This system replaces the factory secondary catalyst with a resonated bypass pipe, designed to fit OE downpipes and Milltek Axle Back systems only. Direct factory fitment with OEM hangers — no modification required. Constructed from T304L stainless steel with mandrel-bent piping, the resonated design is tuned to the G8X platform's natural resonance point, delivering a refined yet sportier exhaust character at full throttle while minimizing drone in cruise. Pipe diameter: 3.00" (76.2mm). Engineered to exhilarate without compromise. Fitment • BMW M3 G80 (2021–present) • BMW M4 G82/G83 (2021–present) • Requires OE or Milltek downpipes • Compatible with Milltek Axle Back systems Built in-house from raw material to finished component. Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.

Fits 14 vehicles including:

• 2021 BMW M3— G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
• 2022 BMW M3— G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
• 2023 BMW M3— G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
• 2024 BMW M3— G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
• 2025 BMW M3— G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
• 2026 BMW M3— G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
• + 8 more vehicles