BMW 5 Series Gran Turismo (2016) is 626 mm (24.65 inch) longer, 101 mm (3.98 inch) wider, 266 mm (10.47 inch) higher and has 338 liters (11.94 ft3) bigger cargo space than Porsche Cayman (2019).
Porsche Cayman (2019) is 510 kg (1,124 lbs) lighter than BMW 5 Series Gran Turismo (2016).