Hi Otto,
The car in question is an Australian speedway speedcar from the mid-1960s. The driver is 'Leadfoot' Len Brock, and the car is the famous McGee Racing Cams special. The photo was probably taken at the famous Sydney Showground. The trophy could be for the Craven - A season pointscore.
The 6 carburettors tells me that the car is running a 6 cylinder Holden engine, rather than an Offenhauser engine. McGee's business was camshaft grinding, and he was elected to the Australian Speedway Hall of Fame a few years ago.