A high-pressure Zoller supercharger was fitted giving a boost to 2.5 atmospheres (1.8 kg/cc) and allowing the engine to produce  at 7200 rpm. A sprint version was also made with output increased to  which at nearly  per litre was the highest specific output of any engine in the world at the time
A high-pressure Zoller supercharger was installed, resulting in a boost of 2.5 atmospheres (1.8 kg/cc) and enabling the engine to produce at 7200 rpm. A sprint version was also created with an output increased to  which was nearly per litre, the highest specific output of any engine globally at that time.