BMW M57 Crankcase Ventilation Adapter The BMW M57 crankcase ventilation adapter is designed for custom M57 engine swap and performance applications where the factory crankcase ventilation layout needs to be modified, simplified or connected to a custom breather system. This adapter can be used when building a standalone M57 setup, custom intake system, top mount turbo layout or engine conversion where the original BMW engine bay packaging is no longer suitable. Typical use cases BMW M57 engine swap projects Custom crankcase ventilation routing Catch can or oil separator installation Top mount turbo conversions Standalone M57 engine installations Off-road, overland and restomod builds Key features Designed for BMW M57 diesel engine applications Allows custom crankcase breather routing Suitable for modified engine bay layouts Useful for swap, retrofit and performance builds Supports cleaner and more serviceable ventilation plumbing This part is intended for custom builds and should be selected according to the exact engine version, ventilation layout and hose routing used in the project.