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  • Specs128ti · 420i

BMW 128ti F40 vs BMW 420i Steptronic Gran Coupe G22: which is truly faster?

Simulated drag race 0 → 1,000 m in real time. Synchronised speed counters and stopwatch. Physics calibration on 7 manufacturer measurements.

compact · 2020 vs 2021 · Methodology
BMWPetrolFaster

128ti F40

265 hp · 400 Nm · 1,445 kg · 2020

VS
BMWPetrol

420i Steptronic Gran Coupe G22

184 hp · 270 Nm · 1,570 kg · 2021

Result · 0–100 km/h

ABMW 128ti F40

6.27 s

Gap1.35 sin favour of 128ti
BBMW 420i Steptronic Gran Coupe G22

7.62 s

Summary · Caralogy simulation
Measure128ti F40420i Steptronic Gran Coupe G22Gap
0–100 km/h6.27 s7.62 s1.35 s · 128ti F40
400 m standing start14.44 s15.55 s1.11 s · 128ti F40
1,000 m standing start25.87 s28.34 s2.47 s · 128ti F40
Top speed (electronically limited)250 km/h236 km/h14 km/h · 128ti F40
Power-to-weight ratio5.45 kg/hp8.53 kg/hpbetter ratio · 128ti F40

Watch the race

Standing-start drag race, calibrated on manufacturer splits. The gap shows at each stage.

BMWPetrol128ti F40
Speed
0km/h
Timer
0,00s
Distance
0m
BMWPetrol420i Steptronic Gran Coupe G22
Speed
0km/h
Timer
0,00s
Distance
0m
100 m
200 m
300 m
400 m
500 m
600 m
700 m
800 m
900 m
1000 m
0m → 1000m
Gap0m

Stage-by-stage comparison

Simulated performance at each stage. Best value in bold.
Stage128ti F40420i Steptronic Gran Coupe G22
0–30 km/h1.81 s1.65 s
0–50 km/h3.01 s2.79 s
0–80 km/h4.76 s5.28 s
0–100 km/h6.27 s7.62 s
0–120 km/h8.20 s10.51 s
0–160 km/h13.63 s19.00 s
0–200 km/h22.97 s34.76 s
400 m standing start14.44 s15.55 s
1,000 m standing start25.87 s28.34 s
Top speed limited250 km/h236 km/h

Parameters and assumptions

Simulation

Start
Standing, straight line
Surface
Dry asphalt, 23°C
Wind
None
Driver
1 person, 75 kg

Calibration

Splits
0–100, 0–200 manufacturer
Power curve
Real measurement (Caralogy)
VMax
Manufacturer limited
Transmission
Losses integrated in model

Physics model calibrated on manufacturer splits. The limited top speed is not the real aerodynamic top speed of the vehicles.

Under the bonnet

Manufacturer technical specifications. The power-to-weight ratio is the key physical factor in a drag race.

BMW

128ti F40

5,45kg/hpratio better by 3,08 kg/hp
CharacteristicValueDetail
Power265 hp4 cyl
Torque400 Nm
Weight1 445 kgmanufacturer kerb weight
Drivetrain-
GearboxEight-speed Steptronic Sport transmission
BMW

420i Steptronic Gran Coupe G22

8,53kg/hpcompensated by −125 kg
CharacteristicValueDetail
Power184 hp4 cyl
Torque270 Nm
Weight1 570 kgmanufacturer kerb weight
Drivetrain-
Gearbox8-speed Steptronic

The start: 0 to 100 km/h

Off the line, the 128ti hits 100 km/h in 6.27 s versus 7.62 s for the 420i Steptronic Gran Coupe. At this point, the 128ti leads by 1.35 s and sits roughly 2 m ahead.

From 100 km/h to 400 metres

At 200 metres, the 128ti is doing 132 km/h against 118 km/h for the 420i Steptronic Gran Coupe. The gap is 0.50 s. The challenger starts to claw back ground.

At 400 metres standing start, the 128ti crosses the line in 14.44 s versus 15.55 s. The 1.11 s gap represents roughly 44 m of track - a gap visible to the naked eye.

Beyond 400 metres: top speed comes into play

Past 400 metres, the 128ti continues to build its lead. At 600 metres, it runs at 184 km/h versus 164 km/h. At 1,000 metres, the 128ti finishes in 25.86 s versus 28.34 s, with a 2.48 s lead. Both vehicles have similar top speeds (250 (i.e. 155 mph - industry threshold) vs 236 km/h), preventing any comeback.

What the numbers don’t tell you

Both rivals are electronically governed, but not at the same level: the 128ti is capped at 250 (i.e. 155 mph - industry threshold) km/h, the 420i Steptronic Gran Coupe at 236 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.

With two combustion powertrains, the difference comes down to power-to-weight ratio (5.45 kg/hp vs 8.53 kg/hp) and transmission (Automatic vs Automatic).

In European road use (130 km/h max), both vehicles reach the legal speed limit in under 12.25 seconds. The 1.35 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.

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Frequently asked questions

Over 0–100 km/h, 128ti F40 wins (6,27 s vs 7,62 s).

128ti F40 goes from 0 to 100 km/h in 6,27 seconds (calibrated simulation).

128ti F40: 265 hp, ratio 5,45 kg/hp. 420i Steptronic Gran Coupe G22: 184 hp, ratio 8,53 kg/hp.

128ti F40: 250 km/h. 420i Steptronic Gran Coupe G22: 236 km/h.