BMW 840i xDrive Convertible G15 vs Cupra Born: which is truly faster?

Off the line, the 840i xDrive Convertible hits 100 km/h in 5.30 s versus 7.23 s for the Born. Despite lacking instant torque, 333 hp of power compensates. At this point, the 840i xDrive Convertible leads by 1.93 s and sits roughly 20 m ahead.

At 200 metres, the 840i xDrive Convertible is doing 136 km/h against 122 km/h for the Born. The gap is 1.24 s. The challenger starts to claw back ground.

At 400 metres standing start, the 840i xDrive Convertible crosses the line in 13.56 s versus 15.39 s. The 1.83 s gap represents roughly 74 m of track - a gap visible to the naked eye.

Past 400 metres, the 840i xDrive Convertible continues to build its lead. At 600 metres, it runs at 190 km/h versus 160 km/h. At 1,000 metres, the 840i xDrive Convertible finishes in 24.59 s versus 28.98 s, with a 4.39 s lead.

The 840i xDrive Convertible features all-wheel drive (AWD) against the Born’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 840i xDrive Convertible is capped at 250 (i.e. 155 mph - industry threshold) km/h, the Born 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 11.41 seconds. The 1.93 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.