Porsche Cayenne S E-Hybrid 958.2 vs BMW X3 M40d G01: which is truly faster?

Off the line, the Bmw X3 M40d hits 100 km/h in 4.99 s versus 5.57 s for the Cayenne S E-Hybrid. Despite lacking instant torque, 340 hp of power compensates. At this point, the Bmw X3 M40d leads by 0.58 s and sits roughly 3 m ahead.

At 200 metres, the Bmw X3 M40d is doing 137 km/h against 131 km/h for the Cayenne S E-Hybrid. The gap is 0.28 s. The challenger starts to claw back ground.

At 400 metres standing start, the Bmw X3 M40d crosses the line in 13.34 s versus 13.82 s. The 0.48 s gap represents roughly 22 m of track - two to three car lengths.

Past 400 metres, the Bmw X3 M40d continues to build its lead. At 600 metres, it runs at 189 km/h versus 180 km/h. At 1,000 metres, the Bmw X3 M40d finishes in 24.47 s versus 25.54 s, with a 1.07 s lead. Both vehicles have similar top speeds (237 vs 250 (i.e. 155 mph - industry threshold) km/h), preventing any comeback.

Both rivals are electronically governed, but not at the same level: the Cayenne S E-Hybrid is capped at 243 km/h, the Bmw X3 M40d 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 8.76 seconds. The 0.58 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.