BMW 5 Series (2020) is 565 mm (22.24 inch) longer, 67 mm (2.64 inch) wider, 185 mm (7.28 inch) higher and has 368 liters (13.00 ft3) bigger cargo space than Porsche Cayman (2014).
Porsche Cayman (2014) is 279 kg (615 lbs) lighter than BMW 5 Series (2020).