For the 1990 season, the car was updated, becoming the FW13B. It featured revised sidepods and suspension upgrades, as well as Renault's RS2 3.5-litre V10 engine. The FW13B proved fast and reliable, with Patrese and Boutsen winning one race each – Patrese at "home" in San Marino (the San Marino Grand Prix was actually run at the Imola Circuit in Italy as the small Republic of San Marino did not have enough land for a race circuit), and Boutsen in Hungary after also claiming pole position. In the latter race, Patrese completed an all-Williams front row, drove the fastest race lap and finished fourth, giving the team plenty to celebrate that weekend. However, the team fell to fourth in the Constructors' Championship, behind Ferrari (with whom Alain Prost challenged for the Drivers' Championship) and Benetton (which won the final two races of the season thanks to former Williams driver Nelson Piquet).