BMW 7 Series (2020) is 728 mm (28.66 inch) longer, 101 mm (3.98 inch) wider, 172 mm (6.77 inch) higher and has 365 liters (12.89 ft3) bigger cargo space than Porsche 718 Cayman (2017).
Porsche 718 Cayman (2017) is 574 kg (1,265 lbs) lighter than BMW 7 Series (2020).