Dinan Turbo Inlet Pipes — F9X M5/M8 (2018–2021)

The gains come down to volume and geometry. Each inlet delivers 105 cubic inches of internal airflow capacity versus the stock unit's 35 cubic inches — a 200% increase that fundamentally changes how much air the turbos can draw under boost. The internal diameter is expanded to the absolute maximum the fitment envelope permits, meaning there's no compromise between clearance and cross-sectional area. Under hard acceleration, the S63 is no longer restricted by its own intake path.

Dinan chose carbon fiber for more than aesthetics. The material's low thermal conductivity helps insulate incoming air charge from the heat-dense engine bay environment, keeping intake temps in check where an aluminum or plastic alternative would absorb and transfer heat. The finished surface also looks intentional and clean for anyone pulling back the hood.

Fitment is specific to 2018–2021 F9X M5 and M8 models and installs without modification to surrounding components. Dinan's engineering reputation is built on parts that fit correctly the first time and perform exactly as advertised — this inlet kit is a direct reflection of that standard.