This decrepit Volvo PV544 has been given new life with the addition of a massive 38.88-liter diesel V12. Built by Swedish engineer Victor Jönsson, and detailed in a series of forum posts, the Volvo has been a special project four years in the making.

Jönsson started this build by purchasing the giant engine from a local military museum. Soviet-designed, the diesel power-plant was first used in the post-World War II T-54 Russian tank, and this particular engine came from a "Stridsvagn" Swedish military vehicle. The V12 was state-of-the-art in its introduction, as it features a water-cooled aluminum block, a dry sump system, dual overhead camshafts, and four valves per cylinder. Output is about 520 horsepower at the crank, giving it a power-to-displacement ratio eclipsed by the original VW Beetle. That figure is all thanks to the engine's low redline of 2000 RPM. When you're driving a heavy steel tank, torque is all that really matters, and this V12 comes with 1,700 pound-feet.