Table:
text: 1961 Formula One season
Teams and drivers
Teams and drivers
Entrant Constructor_ Chassis Engine Tyre Driver Rounds
Owen Racing Organisation BRM - Climax P48/57 Climax FPF 1.5 L4 D Tony Brooks All
Owen Racing Organisation BRM - Climax P48/57 Climax FPF 1.5 L4 D Graham Hill All
R.R.C. Walker Racing Team Lotus - Climax 18 18/21 21 Climax FPF 1.5 L4 D Stirling Moss All
R.R.C. Walker Racing Team Ferguson - Climax P99 Climax FPF 1.5 L4 D Stirling Moss 5
R.R.C. Walker Racing Team Ferguson - Climax P99 Climax FPF 1.5 L4 D Jack Fairman 5
Yeoman Credit Racing Team Cooper - Climax T53 Climax FPF 1.5 L4 D John Surtees All
Yeoman Credit Racing Team Cooper - Climax T53 Climax FPF 1.5 L4 D Roy Salvadori 4–8

Question: What chassis was used by the teams and drivers of Roy Salvadori's 1961 Formula 1 season?