Skip to main content
CaralogyCaralogy
HomeBrandsRoad TripBudgetDuelGuides
Caralogy

The car comparison platform. Physics simulation, road trips, real costs.

Navigation
All brandsCar duelRunning costsMotorwayMethodology
Simulators
Motorway simulatorRunning costsPerformance duel
Brands
VolkswagenBMWMercedesToyotaTeslaAudi
FRENDEESIT
© 2026 Caralogy · All rights reserved
  1. Home
  2. /Duel
  3. /Sedans
AM240ivsB840iPetrol
  • MotorwayMotorwayRange and charging
  • PerformancePerformance0-100, top speed
  • ConsumptionConsumptionYearly cost
  • SpecsM240i · 840i

BMW M240i F44 vs BMW 840i Convertible G15: 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

M240i F44

340 hp · 500 Nm · 1,525 kg · 2020

VS
BMWPetrol

840i Convertible G15

333 hp · 500 Nm · 1,840 kg · 2021

Result · 0–100 km/h

ABMW M240i F44

4.67 s

Gap0.91 sin favour of M240i
BBMW 840i Convertible G15

5.57 s

Summary · Caralogy simulation
MeasureM240i F44840i Convertible G15Gap
0–100 km/h4.67 s5.57 s0.91 s · M240i F44
400 m standing start12.78 s13.79 s1.01 s · M240i F44
1,000 m standing start23.04 s24.82 s1.78 s · M240i F44
Top speed (electronically limited)250 km/h250 km/hSame
Power-to-weight ratio4.49 kg/hp5.53 kg/hpbetter ratio · M240i F44

Watch the race

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

BMWPetrolM240i F44
Speed
0km/h
Timer
0,00s
Distance
0m
BMWPetrol840i Convertible G15
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.
StageM240i F44840i Convertible G15
0–30 km/h1.33 s1.54 s
0–50 km/h2.21 s2.50 s
0–80 km/h3.53 s4.11 s
0–100 km/h4.67 s5.57 s
0–120 km/h6.03 s7.39 s
0–160 km/h9.80 s12.34 s
0–200 km/h15.53 s19.98 s
400 m standing start12.78 s13.79 s
1,000 m standing start23.04 s24.82 s
Top speed limited250 km/h250 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

M240i F44

4,49kg/hpratio better by 1,04 kg/hp
CharacteristicValueDetail
Power340 hpPending
Torque500 Nm
Weight1 525 kgmanufacturer kerb weight
Drivetrain-
Gearbox8-speed Steptronic Sport transmission
BMW

840i Convertible G15

5,53kg/hpcompensated by −315 kg
CharacteristicValueDetail
Power333 hp6 cyl
Torque500 Nm
Weight1 840 kgmanufacturer kerb weight
Drivetrain-
Gearbox8-speed Steptronic

The start: 0 to 100 km/h

Off the line, the M240i hits 100 km/h in 4.67 s versus 5.57 s for the 840i Convertible. At this point, the M240i leads by 0.91 s and sits roughly 8 m ahead.

From 100 km/h to 400 metres

At 200 metres, the M240i is doing 147 km/h against 136 km/h for the 840i Convertible. The gap is 0.65 s. The challenger starts to claw back ground.

At 400 metres standing start, the M240i crosses the line in 12.78 s versus 13.79 s. The 1.01 s gap represents roughly 47 m of track - a gap visible to the naked eye.

Beyond 400 metres: top speed comes into play

Past 400 metres, the M240i continues to build its lead. At 600 metres, it runs at 205 km/h versus 190 km/h. At 1,000 metres, the M240i finishes in 23.03 s versus 24.82 s, with a 1.79 s lead. Both vehicles have similar top speeds (250 (i.e. 155 mph - industry threshold) vs 250 (i.e. 155 mph - industry threshold) km/h), preventing any comeback.

What the numbers don’t tell you

Both rivals share the same electronic speed cap: the M240i and the 840i Convertible 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.

With two combustion powertrains, the difference comes down to power-to-weight ratio (4.49 kg/hp vs 5.53 kg/hp) and transmission (Automatic vs Automatic).

In European road use (130 km/h max), both vehicles reach the legal speed limit in under 8.44 seconds. The 0.91 s difference in 0 to 100 km/h is mostly felt in motorway merging and overtaking.

Other duels you might be interested in

BMWVSAudi

M240i vs S3 Sedan

PorscheVSBMW

Panamera vs 840i Convertible

BMWVSAudi

M240i vs S3 Sportback

BMWVSPorsche

840i Convertible vs Panamera 4

Frequently asked questions

Over 0–100 km/h, M240i F44 wins (4,67 s vs 5,57 s).

M240i F44 goes from 0 to 100 km/h in 4,67 seconds (calibrated simulation).

M240i F44: 340 hp, ratio 4,49 kg/hp. 840i Convertible G15: 333 hp, ratio 5,53 kg/hp.

M240i F44: 250 km/h. 840i Convertible G15: 250 km/h.