Like all engines of that time, the previous Maybach design, the Mb IV, lost at high altitude as much as half of the nominal power of 240 horsepower. The new Maybach Mb IVa of 1916 was the first engine designed to overcome this limitation. It did not use a supercharger, but a much more primitive solution. The engine had purposely oversized cylinders, and a significantly higher 6.08:1 compression ratio. It was tested on Wendelstein (mountain) at an altitude of 1800 m and rated there at 245 hp. This would theoretically correspond to rating of about 300 hp at sea level; however, the engine was not designed to withstand such power - it needed to be carefully throttled down at low altitude, so it would not exceed the safe level of 245 hp. It had three carburettor settings, to be changed during the flight depending on the altitude.