Smallest functional V12 engine

Spanish engineering enthusiast José Manuel Hermo Barreiro (known as "Patelo") has created the smallest working V12 in the world. Taking a total of 1,220 hours (51 days) to construct – and built from bronze, steel and aluminium – the tiny engine is fully functional and runs exactly like a full-sized version. Unlike larger sports car engines, this engine has a displacement of only 12 cu cm (0.73 cu in), with a cylinder diameter of only 11.3 mm and compression stroke of 10 mm. This engine runs on compressed air to avoid creating pollution at the exhibitions and demonstrations it attends. The complete engine is constructed from 261 handcrafted pieces, together with 222 screws that hold everything together.