BMW 120d xDrive F40 vs BMW i3s I01: which is truly faster?

Off the line, the i3s hits 100 km/h in 6.81 s versus 7.21 s for the 120d xDrive. The instant torque of 270 Nm from the electric motor makes the difference. Despite the faster sprint time, the 120d xDrive is 4 m further along the track at this moment: stronger low-speed acceleration offsets a slower run beyond 100 km/h.

At 200 metres, the i3s is doing 124 km/h against 119 km/h for the 120d xDrive. The gap is 0.01 s. The challenger starts to claw back ground.

At 400 metres standing start, the i3s crosses the line in 15.05 s versus 15.27 s. The 0.22 s gap represents roughly 9 m of track - barely a car length.

Past 400 metres, the situation changes. The i3s maxes out at 160 km/h while the 120d xDrive keeps accelerating towards 227 km/h. At 600 metres, the gap has dropped to 0.30 s.

Around 810 metres, both vehicles are level. This is the inversion point: the 120d xDrive overcomes its launch deficit thanks to a 67 km/h higher top speed.

At 1,000 metres, the 120d xDrive finishes in 28.08 s versus 28.59 s. The 0.51 s delta in favour of the 120d xDrive shows that top speed makes a clear difference.

The 120d xDrive features all-wheel drive (AWD) against the i3s’s RWD. At low speeds (0-30, 0-50, 0-80 km/h), AWD doubles the driven contact area: all four wheels transmit torque to the road, virtually eliminating wheelspin at launch. This traction advantage is decisive in the range where the motor delivers peak torque, before power and aerodynamics take over.

Both rivals are electronically governed, but not at the same level: the 120d xDrive is capped at 230 km/h, the i3s at 160 km/h. This isn’t a physical engine limit - it’s a manufacturer choice, usually for tyre safety or homologation reasons. Neither car reaches its true aerodynamic top speed.

Instant electric torque gives an advantage off the line. The higher top speed of the combustion engine gives an advantage over longer distances. The distance at which one catches the other depends on the top speed differential.

In European road use (130 km/h max), both vehicles reach the legal speed limit in under 11.79 seconds. The 0.40 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.