BMW X5 M50i G05 vs BYD Seal 390 AWD: which is truly faster?

Off the line, the Seal 390 AWD hits 100 km/h in 3.77 s versus 4.34 s for the X5 M50i. The instant torque of 670 Nm from the electric motor makes the difference. At this point, the Seal 390 AWD leads by 0.57 s and sits roughly 6 m ahead.

At 200 metres, the Seal 390 AWD is doing 155 km/h against 150 km/h for the X5 M50i. The gap is 0.43 s. The challenger starts to claw back ground.

At 400 metres standing start, the Seal 390 AWD crosses the line in 11.93 s versus 12.43 s. The 0.50 s gap represents roughly 26 m of track - two to three car lengths.

Past 400 metres, the situation changes. The Seal 390 AWD maxes out at 180 km/h while the X5 M50i keeps accelerating towards 250 (i.e. 155 mph - industry threshold) km/h. At 600 metres, the gap has dropped to 0.14 s.

Around 646 metres, both vehicles are level. This is the inversion point: the X5 M50i overcomes its launch deficit thanks to a 70 km/h higher top speed.

At 1,000 metres, the X5 M50i finishes in 22.50 s versus 23.93 s. The 1.43 s delta in favour of the X5 M50i shows that top speed makes a clear difference.

Both rivals are electronically governed, but not at the same level: the X5 M50i is capped at 250 (i.e. 155 mph - industry threshold) km/h, the Seal 390 AWD at 180 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 6.38 seconds. The 0.57 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.