BMW X7 (2018) is 759 mm (29.88 inch) longer, 199 mm (7.83 inch) wider, 510 mm (20.08 inch) higher and has 600 liters (21.19 ft3) bigger cargo space than Porsche 718 Cayman (2017).
Porsche 718 Cayman (2017) is 1014 kg (2,235 lbs) lighter than BMW X7 (2018).