BMW ActiveHybrid X6 E71 vs Mercedes E 400 e 4MATIC W214: which is truly faster?

Off the line, the E 400 e 4MATIC hits 100 km/h in 5.31 s versus 5.60 s for the ActiveHybrid X6. The instant torque of 650 Nm from the electric motor makes the difference. At this point, the E 400 e 4MATIC leads by 0.29 s and sits roughly 11 m ahead.

At 200 metres, the E 400 e 4MATIC is doing 135 km/h against 141 km/h for the ActiveHybrid X6. The gap is 0.30 s. The gap remains stable from the start.

At 400 metres standing start, the E 400 e 4MATIC crosses the line in 13.57 s versus 13.66 s. The 0.10 s gap represents roughly 5 m of track - barely a car length.

Past 400 metres, the situation changes. The ActiveHybrid X6 maxes out at 236 km/h while the E 400 e 4MATIC keeps accelerating towards 250 (i.e. 155 mph - industry threshold) km/h. At 600 metres, the gap has dropped to 0.07 s.

Around 510 metres, both vehicles are level. This is the inversion point: the ActiveHybrid X6 overcomes its launch deficit thanks to a 14 km/h higher top speed.

At 1,000 metres, the ActiveHybrid X6 finishes in 24.29 s versus 24.58 s. The 0.29 s delta shows an extremely tight race.

Both rivals are electronically governed, but not at the same level: the ActiveHybrid X6 is capped at 236 km/h, the E 400 e 4MATIC 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 8.31 seconds. The 0.29 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.