Xpeng X9 vs Alfa Romeo Giulia Quadrifoglio: which is truly faster?

Off the line, the X9 hits 100 km/h in 3.88 s versus 3.93 s for the Giulia Quadrifoglio. The instant torque of 717 Nm from the electric motor makes the difference. The 0.05 s gap is negligible: both vehicles are neck and neck.

At 200 metres, the X9 is doing 173 km/h against 164 km/h for the Giulia Quadrifoglio. The gap is 0.22 s. The gap widens compared to the 0-100.

At 400 metres standing start, the X9 crosses the line in 11.34 s versus 11.73 s. The 0.39 s gap represents roughly 22 m of track - two to three car lengths.

Past 400 metres, the situation changes. The X9 maxes out at 200 km/h while the Giulia Quadrifoglio keeps accelerating towards 307 km/h. At 600 metres, the gap has dropped to 0.11 s.

Around 645 metres, both vehicles are level. This is the inversion point: the Giulia Quadrifoglio overcomes its launch deficit thanks to a 107 km/h higher top speed.

At 1,000 metres, the Giulia Quadrifoglio finishes in 20.92 s versus 22.13 s. The 1.22 s delta in favour of the Giulia Quadrifoglio shows that top speed makes a clear difference.

Both rivals are electronically governed, but not at the same level: the X9 is capped at 200 km/h, the Giulia Quadrifoglio at 307 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 5.50 seconds. The 0.05 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.