Audi S6 Sportback e-tron vs BMW M3 Competition xDrive G80: which is truly faster?

Off the line, the M3 Competition xDrive hits 100 km/h in 3.52 s versus 4.08 s for the S6 Sportback e-tron. Despite lacking instant torque, 510 hp of power compensates. At this point, the M3 Competition xDrive leads by 0.55 s and sits roughly 7 m ahead.

At 200 metres, the M3 Competition xDrive is doing 161 km/h against 146 km/h for the S6 Sportback e-tron. The gap is 0.57 s. The gap remains stable from the start.

At 400 metres standing start, the M3 Competition xDrive crosses the line in 11.45 s versus 12.52 s. The 1.07 s gap represents roughly 51 m of track - a gap visible to the naked eye.

Past 400 metres, the M3 Competition xDrive continues to build its lead. At 600 metres, it runs at 224 km/h versus 191 km/h. At 1,000 metres, the M3 Competition xDrive finishes in 20.83 s versus 23.58 s, with a 2.75 s lead.

Both rivals are electronically governed, but not at the same level: the S6 Sportback e-tron is capped at 240 km/h, the M3 Competition xDrive at 250 (i.e. 155 mph - industry threshold) 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 6.31 seconds. The 0.55 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.