BMW 3 Series Touring (2016) is 90 mm (3.54 inch) higher, 283 kg (624 lbs) lighter and has 145 liters (5.12 ft3) bigger cargo space than BMW 8 Series (G14) (2018).
BMW 8 Series (G14) (2018) is 210 mm (8.27 inch) longer and 91 mm (3.58 inch) wider than BMW 3 Series Touring (2016).