[quantumsolace]

Let me quote my Math Phys professor:

"You're utterly and completely wrong."

Let's assume we're talking about acceleration due to change of direction, or braking (since for increasing speed weight is obviously a disadvantage you simply decided to disregard)

The force required to change car's direction due to change of direction or braking is proportional to weight.

F = m*a

Therefore

(1) a = F/m

The expression for the turning torque is similar

To a first order approximation the maximum traction force available to a car is proportional to the normal force

(2) Ff = u Fg = u m g

Where Fg is force of gravity, and Ff is maximum force of traction.

So, it appears that the mass cancels out. It doesn't:

1. there's the fact that Coloum's law of friction is incorrect, especially for rubber. That's why race cars have wide tyres.

2. aerodynamic downforce is independent of weight. So my expression (2) is wrong.

Ff = u* (m*g + k*v^2)

Where k has all the information about lift.

As you can see mass no longer cancels out. As mass increases the force required to change direction increases proportionally, but the traction force available stays roughly the same.

But it gets worse. Let's say we ignore aerodynamics and assume Coloumb's law of friction (hahahahaha), largely your scenario

In comparing two cars, one double in mass than the other, the heavier car will wear out tires more quickly (since they're subject to double the loads). The heavier car will run the breaks hotter and be more prone to fading.

There is nothing good about added mass for the dynamics of a car. Nothing.*

[elif]

No... the forces required to change a car's direction are friction forces on the tires reaching their limits.... your space calculations dont really mean much unless you are trying to build a rocketship.

[sbakzbsmx]

… he literally wrote Columb’s expression for frictional forces. Then pointed out that that expression overstates the amount of traction that weight gives you

What rules of physics do you propose we use? Ones where dead weight makes you faster? In the ideal case weight cancels out. But it doesn't, it forces you to take corners slower.

But hey, if you don't believe the math, watch an F1 race how the lap times drop and tyre life extends as they use up their fuel.