Take your N54-powered BMW 135i to the next level with ARM Motorsports' 3" catless downpipes. 

The ARM N54 catless downpipes eliminate the restrictive oem converters on the stock downpipes allowing the exhaust to flow more freely, increasing power and torque. Because higher boost levels generate more heat, the ARM catless downpipes allows your 135i to run boost settings of Stage 2 tunes and beyond. 

  

CONSTRUCTION

The ARM 135i catless downpipes are designed with a 3" stainless steel construction to optimize exhaust flow and obtain optimal back-pressure. Each downpipe has 2x O2 sensor bungs so the factory BMW O2 sensors can be remounted, allowing the ECU to continue to monitor the exhaust gases. Because these downpipes are a catless design, an ECU tune or CEL fix will be needed to avoid a CEL from displaying on instrument panel.