The launch is a traction problem
An electric motor can produce strong pulling force from the moment it begins turning, but that force reaches the road through four small tire contact patches. If the wheels demand more grip than the pavement can provide, they spin instead of pushing the car forward. The limiting factor in a launch is therefore not simply how much power the motors can make; it is how precisely the car can use the grip available.
A very light prototype has an advantage because it needs less force to gain speed than a heavier car. But lightness does not eliminate the tire limit. The motors’ output must be managed so the tires keep biting as speed rises and the car’s load shifts during acceleration.
Why test in a tunnel?
A controlled tunnel gives engineers a repeatable place to examine that brief, difficult launch. When the surroundings and test setup are kept consistent, a run can be measured and compared with another without the many changing conditions of an open road. That helps the team distinguish a genuine improvement in the car’s acceleration from a difference in the test itself.
The tunnel does not make the surface grip better by magic, or make the result effortless: the car still has to transfer its force to the ground. The achievement is not just producing a huge initial shove, but turning it into forward motion without wasting it in wheelspin. A sub-two-second sprint is over almost as soon as it begins, which makes controlling those first moments the central engineering challenge.
