BMW Engine Platform · Petrol
BMW N55 3.0L Turbo I6
The N55 replaced the twin-turbo N54 in 2009, adopting a single twin-scroll turbocharger for improved efficiency and response. It powers the F30 335i, F22 M235i, F20 M135i/M140i, and many X models. Widely regarded as one of BMW's most rewarding engines to tune.
ECU Ecosystem
Siemens MEVD17.2 on most applications. OBD reading and writing is well-supported across all variants, making it one of the easiest modern BMW engines to calibrate remotely.
Fuel Considerations
98 RON minimum. The N55 benefits noticeably from higher octane fuel. E85 compatibility exists but requires fuelling hardware upgrades.
Stage 1 Path
Stage 1 delivers 340-370 hp and 500-540 Nm with no hardware changes on 98 RON. The single twin-scroll turbo responds beautifully to boost and timing adjustments.
Stage 2 Path
Stage 2 with downpipe and upgraded intercooler reaches 380-410 hp. For higher targets, a pure turbine housing upgrade or hybrid turbo opens the door to 450+ hp builds.
Reliability Considerations
Reliable when maintained. Known issues include valve cover gasket leaks, oil filter housing gasket leaks, and wastegate rattle at higher mileages. The OFHG should be addressed before tuning to prevent coolant contamination.
BMW Models with N55
Dyno Case Studies
Related BMW Resources
Need a file for the N55?
Submit your ECU read through the JB Remap File Service Portal.