The 2006 Porsche 911 tire size depends on trim: the Carrera 4, 2D Convertible, Automatic takes 235/40ZR18 (91Y); the Carrera 4S, 2D Convertible, Standard takes 235/35ZR19 (87Y); the Carrera 4, 2D Coupe, Standard takes 235/40ZR18 (91Y); the Carrera 4S, 2D Convertible, Automatic takes 235/35ZR19 (87Y); the Carrera 4, 2D Convertible, Standard takes 235/40ZR18 (91Y); the Carrera 4S, 2D Coupe, Automatic takes 235/35ZR19 (87Y); the Carrera 4, 2D Coupe, Automatic takes 235/40ZR18 (91Y); the Carrera 4S, 2D Coupe, Standard takes 235/35ZR19 (87Y); the Carrera, 2D Coupe, Automatic takes 235/40ZR18 (91Y); the Carrera S, 2D Coupe, Standard takes 235/35ZR19 (87Y); the Carrera S, 2D Coupe, Automatic takes 235/35ZR19 (87Y); the Carrera S, 2D Convertible, Automatic takes 235/35ZR19 (87Y); the Carrera S, 2D Convertible, Standard takes 235/35ZR19 (87Y); the Carrera, 2D Coupe, Standard takes 235/40ZR18 (91Y); the Carrera, 2D Convertible takes 235/40ZR18 (91Y), per the factory service manual.
Factory-Spec Tire Size
Varies by trim
Carrera 4, 2D Convertible, Automatic: 235/40ZR18 (91Y)
Carrera 4S, 2D Convertible, Standard: 235/35ZR19 (87Y)
Carrera 4, 2D Coupe, Standard: 235/40ZR18 (91Y)
Carrera 4S, 2D Convertible, Automatic: 235/35ZR19 (87Y)
Carrera 4, 2D Convertible, Standard: 235/40ZR18 (91Y)
Carrera 4S, 2D Coupe, Automatic: 235/35ZR19 (87Y)
Carrera 4, 2D Coupe, Automatic: 235/40ZR18 (91Y)
Carrera 4S, 2D Coupe, Standard: 235/35ZR19 (87Y)
Carrera, 2D Coupe, Automatic: 235/40ZR18 (91Y)
Carrera S, 2D Coupe, Standard: 235/35ZR19 (87Y)
Carrera S, 2D Coupe, Automatic: 235/35ZR19 (87Y)
Carrera S, 2D Convertible, Automatic: 235/35ZR19 (87Y)
Carrera S, 2D Convertible, Standard: 235/35ZR19 (87Y)