Exhaust Fitment Notes

Field notes on aftermarket exhaust fitment and materials

• BMW G20 Fitment: Why 320i, 330i and M340i Need Different Exhaust Parts

  The G20 3 Series shares a body, not an exhaust. Three engines, three pipe diameters, three rear valance shapes.

• How to Read an Exhaust Flange Before You Order a Container

  Flange type decides whether a system bolts on or needs a welder. Four things to measure, and the one most buyers forget.

• Vacuum vs Electronic Exhaust Valves: What Actually Fails

  Both give the owner a quiet mode and a loud mode. They fail in completely different ways, and one of them needs a vacuum source the car may not have.