MakerWorld user Auxcron's incredible 1:2.5 scale reconstruction of the Volkswagen 1.9 TDI engine is a sight to behold. Totalling some 300+ components requiring more than 50 hours of total printing time, the result is a fully animated monument to great fuel economy.
The files aren't publicly available – yet. Auxcron is preparing to launch the project as a crowdfunding campaign on MakerWorld, with the proceeds providing funds and time to improve the fit and finish of the parts, author the build guide and BOM, and generally give it the polish it deserves before releasing the files.