The FX3B was used for the first three races of the 1973 season, and had been driven by New Zealander Howden Ganley and Italian Nanni Galli, although Jackie Pretorius had filled in at the South African Grand Prix when Galli was injured. The new IR appeared at the fourth race of the season, the Spanish Grand Prix, with Ganley and the returning Galli at the wheel. Qualifying on the last two rows of the grid, the Italian finished 11th while Ganley retired when he ran out of fuel. Both drivers retired in Belgium, through an engine failure for Galli and an accident for Ganley when his throttle stuck. Both drivers retired with half-shaft failures at the Monaco Grand Prix, although Ganley had qualified tenth fastest, and after the race Galli left the team and announced his retirement from Formula One.