WHAT IS A CAR?
Lightning McQueen’s friends come in many different shapes and sizes. They are all marvelous machines that use their own power to get from one place to another—or quickly around a racetrack. Let’s take a peek under the hood and explore the amazing machines we call cars.
It’s a Big Group!
Cars are part of the big group of vehicles called automobiles, ormotorized vehicles. In that group, you will find cars, trucks, buses, and vans. You will even find tractors, bulldozers, and fire trucks. There are different kinds of vehicles for different kinds of jobs.
What Every Vehicle Needs
Every vehicle has an engine. The engine uses some kind of fuel for energy. A gasoline engine converts gasoline, or gas, into motion to get a car moving. An engine in an electric vehicle is called a motor. An electric car delivers power from the batteries to the motor.
Let’s Get Rolling!
Fuel runs the engine or motor, which sends power to the wheels. That power makes the wheels move. Let’s find out more about how these great machines work.
CARS TO RACE AND RIDE
Sterling owns the Rust-Eze Racing Center. Cars train there to become better racers. But what exactly makes a car a race car? What does a race car have that a family car or commuter car doesn’t?
A race car like Cruz Ramirez is built for speed! Her body, engine, and tires help her go as fast as she safely can on the racetrack.
A family car or a minivan is not for racing. Its job is to carry you and your friends or family on the road—not on the racetrack. It is built to keep you safe and comfortable.
Any car, except a race car, can be a commuter car. Its main job is to travel from home to work and back every day. Many of the best commuter cars are small, comfortable, and safe.
ALL SYSTEMS GO!
Smokey was the Fabulous Hudson Hornet’s crew chief. If a car is in trouble, he can find the trouble and fix it! Smokey understands that a car is made up of many different systems. All the systems have to work together to keep a car running.
MAKING THE METAL MOVE
Doc was Lightning’s crew chief. Doc knew that every car starts with several main systems—the engine, the drivetrain, the chassis, the steering, and the brakes.
A car without an engine will not move. The engine is the thing that all the other systems count on. The engine provides the power to all the systems in the car.
The engine’s main job is to burn fuel and turn it into energy. That energy is transferred to the drivetrain, which is connected to the back or sometimes the side of the engine. The drivetrain delivers the power produced in the engine to the wheels so the car can move. The gears in the transmission help control how fast or slow the cargoes.
THE BODY AND THE CHASSIS
A chassis is the supporting frame of the car. A car’s engine, tires, and other mechanical parts are bolted to the chassis.
The body of a car is made up of large panels. The body is designed to protect a car’s riders. A car’s engine, transmission, and other systems can sometimes be found within the body.
In many race cars, trucks, and older cars like Doc or Smokey, the chassis and the body are made as two separate pieces and then fastened together. But most cars made today have a unibody design. The frame and the basic body shell are made together. A chassis and body that is one big piece is easier and faster to build. A car with a unibody design is also lighter, quieter, and safer.
FUEL THE MACHINE
Before leaving the Cotter Pin, River Scott stops to fill up at the gasoline pump outside the door. Why? Because gas keeps a car’s engine running! Gas is the fuel still used by most cars today—but that is changing.
Explosive Power Reducing
An engine that uses gas has a special name. It is called an internal combustion engine. Internal means “inside.”Combustion means “burning.” Fuel is pumped into the engine whereat just the right time—a tiny electrical spark sets off an explosion. The force of that explosion is the power that makes the wheels move.
The fuel internal combustion engines burn is not good for our air. More and more cars are being manufactured without internal combustion engines. Their engines use electricity for fuel, not gas. Instead of stopping to fill the car’s gas tank, a driver stops to recharge the car’s big batteries.