was at the height of its powers. Automotive designer Dr.  Ferdinand Porsche  first targeted a speed of 550 km/h (342 mph), but after  George Eyston 's and  John Cobb 's successful  LSR  runs of 1938-39 the target speed was raised to 600 km/h (373 mph). Powered by a massive 44.5 litre  Daimler-Benz DB 603  inverted  V12  the