Mercedes AMG S 63 E Performance W223 vs BMW X3 xDrive30i G01: which is truly faster?

Off the line, the AMG S 63 E Performance hits 100 km/h in 3.27 s versus 6.35 s for the X3 xDrive30i. The instant torque of 1,430 Nm from the electric motor makes the difference. At this point, the AMG S 63 E Performance leads by 3.08 s and sits roughly 19 m ahead.

At 200 metres, the AMG S 63 E Performance is doing 165 km/h against 126 km/h for the X3 xDrive30i. The gap is 2.20 s. The challenger starts to claw back ground.

At 400 metres standing start, the AMG S 63 E Performance crosses the line in 11.12 s versus 14.56 s. The 3.44 s gap represents roughly 141 m of track - a gap visible to the naked eye.

Past 400 metres, the AMG S 63 E Performance continues to build its lead. At 600 metres, it runs at 241 km/h versus 175 km/h. At 1,000 metres, the AMG S 63 E Performance finishes in 20.09 s versus 26.56 s, with a 6.47 s lead. Both vehicles have similar top speeds (250 (i.e. 155 mph - industry threshold) vs 240 km/h), preventing any comeback.

Both rivals are electronically governed, but not at the same level: the AMG S 63 E Performance is capped at 250 (i.e. 155 mph - industry threshold) km/h, the X3 xDrive30i at 240 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 10.01 seconds. The 3.08 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.