Milltek Secondary Cat Bypass | BMW G8X M3 M4

Name: Milltek Secondary Cat Bypass | BMW G8X M3 M4
Brand: Milltek
SKU: SSXBM1341
Price: 1236.92 USD
Availability: InStock

SKU: SSXBM1341

$1236.92 $1236.92

System Type

Milltek secondary catalyst bypass for BMW G8X M3 and M4 (S58). 102mm T304L non-resonated X pipe with dyno-proven power gains. Direct bolt-on to OE or Milltek axle back, no modification needed.

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More info

Z-Pipe upgrade for existing Milltek BMW G80 M3 and G82 M4 secondary catalyst bypass customers. 3D printed 316L stainless. Replaces a Milltek X-Pipe, resonator or twin straight pipes in a 102mm mid-pipe or secondary cat bypass system. Cannot be used on its own. Engineered for the Emotion. - Read More

Parts

Description

102mm single mid pipe non-resonated X pipe secondary catalyst bypass for BMW G8X M3 and M4. Bolts directly to OE axle back (SSXBM1342) or Milltek axle back exhaust (SSXBM1341). Track-focused configuration eliminates secondary catalyst restriction while maintaining OEM+ fitment and hanger compatibility.

Hand-finished T304L stainless steel construction with mandrel-bent piping. Non-resonated design optimized for closed-course and track use. Dyno-proven power gains with engineered tone character across the RPM range.

Fits BMW G8X M3 (S58 engine) and M4 (S58 engine)
Direct bolt-on to OE or Milltek axle back systems
Uses factory hangers and mounting points — no modification required
T304L stainless steel, hand-finished
Mandrel-bent X pipe configuration
Track/closed-course optimized — non-resonated
Valve-compatible for OE secondary valve functionality

In-house manufacturing from raw stainless steel to finished component ensures precision fit and durability.

Designed and manufactured in the UK with 40+ years of performance exhaust heritage. Tested at the Nurburgring.

Key Facts

Pipe Diameter	101.60
1.5 to 2 hours to fit (including removing OE system)
Race Product	Yes
EMarked	No

System Fitment List

- BMW > 3 Series > G80 M3 & M3 Competition S58 3.0 Turbo > 2021 and Later
- BMW > 4 Series > G82 M4 & M4 Competition S58 3.0 Turbo > 2021 and Later