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BMW M5 F90 ECU Tuning Guide — S63 4.4L Twin-Turbo V8 Stage 1, 2 & 3 Power, Mods & GCC Tips (2026)
The BMW M5 F90 is the most potent iteration of BMW's legendary super sedan, powered by the S63B44T4 — a 4.4-litre twin-turbocharged V8 producing 600 HP in standard trim and 625 HP in Competition spec. With boost levels held conservatively from the factory and a robust bottom-end forged rotating assembly, the S63 in the F90 is one of the most rewarding platforms in the BMW M lineup to tune. Stage 1 ECU calibration alone pushes past 700 HP, while full-build Stage 3 configurations regularly exceed 1,000 HP on pump fuel. This guide breaks down every tuning stage, the hardware each...