The M400 is the track variant of the M12 and weighs the same as the GTO3R. It has 425 bhp (317 kW; 431 PS) and has been reported to do 0-60 mph (0–97 km/h) in as little as 2.97 seconds. Car and Driver (March, 2007) achieved a 0-60 mph time of 3.3 seconds and a 0-100 mph time of 7.8 seconds. Noble indicate only that the car is capable of achieving 0-60 mph in under 4.0 seconds. Its top speed is listed as 185 mph (298 km/h). A top speed of 177 mph (285 km/h) has been achieved by Noble's former press officer. Lateral Gs are reported in excess of 1.4.. The model designation M400 is derived from the fact that the power and weight specifications for the car correspond to 405 bhp (302 kW; 411 PS) per tonne. It has both a 3 point seatbelt and a 4 point harness. The most notable differences from the M12 are the use of bigger turbos that generate higher boost, a front anti-roll bar, stiffer springs, different shocks, Pirelli P Zero tyres, a smoother gearchange, different seats, and a slightly narrower central tunnel. The M400 is designed to be an outstanding track car that is also pleasant to drive on the road.