Stage 2 N54 RSS
BMW N54 ECU Tuning Guide — Stage 1 & Stage 2 Power Gains, Cost & Process (2026)
The BMW N54 3.0-liter twin-turbocharged inline-six is one of the most tunable engines BMW has ever built — and it started the modern era of forced-induction BMW performance. Found in the 335i, 535i, 135i, Z4 35i, and X6 35i, the N54 responds to ECU calibration with gains that rival engines costing three times as much. A Stage 2 ECU tune transforms the N54 from a refined luxury engine into a genuine performance weapon — and at $1,299, it's one of the best power-per-dollar upgrades available for any turbocharged platform. This guide covers everything you need to know about ECU tuning...