Wagner Tuning just released a 300 CEL B58 catted downpipe with HJS cats.


This is great news for users with stock , stage 1 or piggyback tunes (which do not clear the CEL code). This downpipe with HJS cats will not throw any CEL while still providing greater air flow than stock.


Please be aware, Wagner Tuning now offer 3 different downpipes for the B58:Catless, catted with 200 CEL, Catted with 300 CEL (HJS Cats)


Downpipe Kit with HJS-ECE-300CPSI Racing catalyst for BMW M140i 340i & 440i



  • made out of high quality stainless steel 1.4301 (SS304)
  • complete Ø3,5 and adapter for stock exhaust
  • HJS (ECE approval) 300CPSI EU6 Racing Metal Catalytic Converter
  • 100% perfect fit, replace OEM
  • less thermal load on the turbocharger
  • more power by reducing back pressure
  • significantly more torque




Air flow chart with all Wagner Tuning downpipe & stock