4.4t-v8 RSS

The BMW XM is BMW M's first dedicated standalone vehicle — a statement-making performance SUV powered by the S68 4.4-liter twin-turbo V8. Whether you own the base XM (644 HP combined) or the XM Label Red (738 HP combined), upgrading the factory downpipes is the most impactful bolt-on modification to unleash the S68's full potential.This guide covers catless and 200-cell downpipe options, power gains, exhaust sound, and why an ECU calibration is required after installation.The S68 4.4T V8 — Platform OverviewThe S68 is BMW's latest-generation 4.4-liter twin-turbocharged V8, featuring a hot-V configuration with 48V mild-hybrid assist. In the XM, it's...

The BMW S63 engine family is one of the most capable twin-turbo V8 platforms ever built. From the F10 M5 to the F90 M5 Competition, and from the M6 Grand Coupé to the X5M and X6M, the S63 in its various iterations has powered BMW's most powerful models for over a decade. Upgrading the factory downpipes is the single most effective bolt-on modification across the entire S63 lineup.This guide covers catless downpipe options for every S63-powered BMW, real-world power gains, exhaust sound changes, fitment across all models, and why an ECU calibration is essential.The S63 Engine Family — Platform OverviewThe...