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

Off the line, the S6 Sportback e-tron hits 100 km/h in 4.08 s versus 4.18 s for the M3 Sedan. The instant torque of 855 Nm from the electric motor makes the difference. At this point, the S6 Sportback e-tron leads by 0.10 s and sits roughly 4 m ahead.

At 200 metres, the S6 Sportback e-tron is doing 146 km/h against 154 km/h for the M3 Sedan. The gap is 0.05 s. The gap remains stable from the start.

At 400 metres standing start, the M3 Sedan crosses the line in 12.25 s versus 12.52 s. The 0.27 s gap represents roughly 13 m of track - two to three car lengths.

Past 400 metres, the M3 Sedan continues to build its lead. At 600 metres, it runs at 216 km/h versus 191 km/h. At 1,000 metres, the M3 Sedan finishes in 21.95 s versus 23.58 s, with a 1.63 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 Sedan 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 0.10 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.