I’ve always hear it when i’m watching about racing cars, i’m a farn of cars but i dont know about naturally aspirated and supercharged engines.
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A car engine mixes gas, oxygen, and spark to create combustion. The air and fuel is mixed in the cylinder and when it explodes it expands, powering the engine. The bigger the explosion, more power. So a bigger engine makes more power than a smaller engine. Also, the more explosions you have, the more power (hence v6, v8, v10, etc).
The ideal ratio of gas and oxygen is 14.7 units of air to 1 unit of fuel. This produces the most efficient combustion and thus the most power. A naturally aspirated engine just draws in air from outside the car, and then adds enough units of fuel to get to that ideal ratio.
Let’s do a simple illustration. Imagine you are holding an empty jar. To make it simple, let’s say it is exactly the correct size to hold 147 air molecules. You take the lid off and let it fill with air, then close the lid. The jar will have 147 air molecules in it. To get the ideal combustion you would have to add 10 fuel molecules. This is how a naturally aspirated engine works. But the power is limited here, you will have a small explosion with only 147 air molecules. If you want a bigger explosion, you need to be able to hold more air molecules. One way is to use a bigger jar. Another way is to get several jars together.
But wait! There is another way. You may recall that air can be compressed. We can actually squeeze more air molecules into the jar. If you pump more air into the jar, now you can fit more molecules of air in there, and then you can pump more molecules of fuel, and get a bigger explosion. That is basically what a turbo or supercharger is, it’s a turbine that pumps more air into the cylinder to get more combustion out of the cylinder, compared to regular non-compressed air that is just hanging outside the car.
Knowing this, we can also understand how altitude affects engine performance, and also how cold air intakes work. The higher you go, the air is less dense, meaning there are less air molecules in a given space. So combustion engines produce less power at higher altitudes. Cold air intakes work off the fact that cold air is more dense than hot air. Since engines produce a lot of heat, they heat up the air near them, so moving the air intake away from the engine will benefit this. However, this is such a small difference that you probably aren’t going to notice it.
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