BMW 7 Series (2018) is 640 mm (25.20 inch) longer, 99 mm (3.90 inch) wider, 208 mm (8.19 inch) higher and has 330 liters (11.65 ft3) bigger cargo space than Porsche 718 Cayman (2021).
Porsche 718 Cayman (2021) is 409 kg (902 lbs) lighter than BMW 7 Series (2018).