BMW 5 Series Gran Turismo (2020) is 254 mm (10.00 inch) longer, 185 mm (7.28 inch) higher and has 376 liters (13.28 ft3) bigger cargo space than BMW i8 (2015).
BMW i8 (2015) is 75 mm (2.95 inch) wider and 185 kg (408 lbs) lighter than BMW 5 Series Gran Turismo (2020).