The P160 debuted at the 1971 South African Grand Prix, where a single entry for Pedro Rodríguez retired with overheating. Jo Siffert, who had driven the P153 in South Africa, switched to the P160 for the remainder of the year.
The season produced two memorable victories. At the Austrian Grand Prix, Siffert took the win. Then at Monza for the Italian Grand Prix, Peter Gethin won in the closest finish in the sport's history: Gethin, Ronnie Peterson, François Cevert, Mike Hailwood, and Howden Ganley crossed the line covered by fractions of a second. Rodríguez had been killed in July during an Interserie sports car race at Norisring before the season's end.
At the United States Grand Prix, Siffert finished second and Ganley fourth — a strong points haul. Siffert died shortly after, at the non-championship World Championship Victory Race at Brands Hatch, when his BRM suffered a mechanical failure at Hawthorn Bend on lap 15, pitching the car into a bank; the car caught fire, trapping the Swiss driver.
BRM ran the updated P160B specification to open 1972 before mid-season introduction of the P160C. Jean-Pierre Beltoise joined Gethin and Ganley, with Reine Wisell also driving. The season's standout result came at Monaco, where Beltoise won in wet conditions — BRM's final Formula One victory. Helmut Marko, entered for the Austrian Grand Prix, was permanently blinded in his left eye at the French Grand Prix when a stone thrown up by Emerson Fittipaldi's Lotus pierced his helmet visor, ending his driving career.
The P160C began the 1973 campaign before successive specification updates (P160D and P160E) arrived mid-year. Beltoise was joined by Niki Lauda and Clay Regazzoni, but the season was difficult. At the South African Grand Prix, Regazzoni was involved in a fiery accident; Mike Hailwood went to pull him from his burning car, sustaining burns himself, and was subsequently awarded the George Medal for his actions.
Lauda retired from most races with mechanical failures and broke his wrist in a suspension failure at the German Grand Prix. Regazzoni scored scattered points including a fourth at Monza in 1972-specification. Beltoise provided the team's most consistent performances, finishing fifth at Spain, Holland, and both Austria and Canada. Lauda and Regazzoni both left at season's end for Ferrari.
With Regazzoni and Lauda departed, Henri Pescarolo and François Migault joined Beltoise for 1974. The P160E continued through most of the year before being replaced by the BRM P201, which would prove to be among the final cars BRM produced as a competitive force.
The P160's victories at Monza 1971 and Monaco 1972 bookended BRM's last winning chapter. The Monza result in particular — achieved in a race of extraordinary closeness involving five manufacturers — remains one of the most dramatic finishes in Formula One history. Southgate's design gave BRM a foundation competitive enough to attract drivers of the calibre of Lauda and Regazzoni, though the team's resources and direction could not sustain the momentum into the mid-1970s. BRM withdrew from Formula One at the end of 1977.