BMW i8 (2017) is 1159 kg (2,555 lbs) lighter than Rolls-Royce Phantom Coupe (2014).
Rolls-Royce Phantom Coupe (2014) is 923 mm (36.34 inch) longer, 45 mm (1.77 inch) wider, 273 mm (10.75 inch) higher and has 157 liters (5.54 ft3) bigger cargo space than BMW i8 (2017).