At first, it doesn’t necessarily seem like a fair fight, as the M4 has 425 hp while the BMW i8 has a combined 357 hp. The M4 also has a six-cylinder engine while the i8 only has three. The M4 has two turbochargers while the i8 has one. So it seems like the M4 has the clear advantage. However, it does even up, as the i8 is around 200 lbs lighter than the M4 and has all-wheel drive to help with the launch off of the line.
The BMW i8 also has the benefit of using electric motors, which provide 100 percent of their torque at zero rpm. This allows the i8 to fire of the line with vicious authority.
The final result is fairly reasonable. The i8 hybrid sportscar ran to 60 mph in 4.4 seconds, two tenths of a second quicker than the M4. It fell behind the coupe on the 100mph run – 9.6 sec vs 9.4 – but the i8 was slightly quicker in the quarter mile sprint – 12.5 sec vs. 12.6.