Audi RS 5 Sedan vs Audi S8: which is truly faster?

Off the line, the RS 5 Sedan hits 100 km/h in 3.73 s versus 3.83 s for the S8. The instant torque of 825 Nm from the electric motor makes the difference. At this point, the RS 5 Sedan leads by 0.10 s and sits roughly 2 m ahead.

At 200 metres, the RS 5 Sedan is doing 156 km/h against 157 km/h for the S8. The gap is 0.08 s. The gap remains stable from the start.

At 400 metres standing start, the RS 5 Sedan crosses the line in 11.77 s versus 11.81 s. The 0.04 s gap represents roughly 2 m of track — barely a car length.

Past 400 metres, the situation changes. Past 400 metres, both rivals hit the same electronic ceiling at 250 (i.e. 155 mph — industry threshold) km/h. Neither can claw back ground through top speed — the outcome hinges on the acceleration curve between 100 and 250 (i.e. 155 mph — industry threshold) km/h.

At 1,000 metres, the S8 finishes in 21.26 s versus 21.38 s. The 0.11 s delta shows an extremely tight race.

Both rivals share the same electronic speed cap: the RS 5 Sedan and the S8 are governed to 250 (i.e. 155 mph — industry threshold) km/h. At that speed, standard-fit tyres approach their safety threshold — an industrial ceiling common to most electric vehicles in this segment. Neither car shows its true aerodynamic potential in this duel.

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 5.62 seconds. The 0.10 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.