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during cornering. Tightly sprung cars, such as sports cars (think Mazda Miata), are less forgiving on bumpy roads, but they minimize body motion well, which means they can be driven aggressively, even around corners.

So, while springs by themselves seem like simple devices, designing and implementing them on a car to balance passenger comfort with handling is a complex task. And to make matters more complex, springs alone can't provide a perfectly smooth ride. Why? Because springs are great at absorbing energy, but not so good at dissipating it. Other structures, known as

СDAMPENING STRUCTURE

dampers, are required to do this.

иwill continue to bounce at its natural frequency until all of the energy originally put into it is used up. A suspension built on springs alone would

Unless a dampening structure is present, a car spring will extend and

spring motionбАthrough a process known as dampening. Shock absorbers slow down and reduce the magnitude of vibratory motions by turning the kinetic energy of suspension movement into heat energy that can be dissipated through hydraulic fluid. To understand how this works, it's best to look inside a shock absorber to see its structure and function.

release the energy it absorbs from a bump at an uncontrolled rate. The spring

make for an extremely bouncy ride and, depending on the terrain, an uncontrollable car.

Enter the shock absorber, or snubber, a device that controls unwanted

wheel (i.e., the unsprung weight)Д. In a twin-tube design, one of the most common types of shock absorbers, the upper mount is connected to a piston

A shock absorber is basically an oil pump placed between the frame of

the car and the wheels. The upper mount of the shock connects to the frame

(i.e., the sprung weight), while the lower mount connects to the axle, near the

rod, which in turn is connected to a piston, which in turn sits in a tube filled with hydraulic fluid. The inner tube is known as the pressure tube, and the outer tube is known as the reserve tube. The reserve tube stores excess

spring to coil and uncoil, the energy of the spring is transferred to the shock absorber through the upper mount, down through the piston rod and into the piston. Orifices perforate the piston and allow fluid to leak through as the piston moves up and down in the pressure tube. Because the orifices are relatively tiny, only a small amount of fluid, under great pressure, passes through. This slows down the piston, which in turn slows down the spring.

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Shock absorbers work in two cycles – the compression cycle and the extension cycle. The compression cycle occurs as the piston moves downward, compressing the hydraulic fluid in the chamber below the piston. The extension cycle occurs as the piston moves toward the top of the pressure tube, compressing the fluid in the chamber above the piston. A typical car or light truck will have more resistance during its extension cycle than its

Сcompression cycle. With that in mind, the compression cycle controls the motion of the vehicle's unsprang weight, while extension controls the heavier, sprung weight.

All modern shock absorbers are velocity-sensitive – the faster the suspension moves, the more resistance the shock absorber provides. This enables shocks to adjust to road conditions and to control all of the unwanted motions that can occur in a moving vehicle, including bounce, sway, brake

иstrut – basically a shock absorber mounted inside a coil spring. Struts perform two jobs: They provide a dampening function like shock absorbers,

dive and acceleration squat.

can allowбАexcessive vehicle-weight transfer from side to side and front to back. This reduces the tire's ability to grip the road, as well as handling and braking performance.

Common strut design. Another common dampening structure is the

and they provide structural support for the vehicle suspension. That means struts deliver a bit more than shock absorbers, which don't support vehicle weight – they only control the speed at which weight is transferred in a car, not the weight itself.

Because shocks and struts have so much to do with the handling of a

car, they can be considered critical safety features. Worn shocks and struts Д

Anti-sway Bars. Anti-sway bars (also known as anti-roll bars) are used

along with shock absorbers or struts to give a moving automobile additional stability. An anti-sway bar is a metal rod thatИspans the entire axle and effectively joins each side of the suspension together.

When the suspension at one wheel moves up and down, the anti-sway bar transfers movement to the other wheel. This creates a more level ride and reduces vehicle sway. In particular, it combats the roll of a car on its suspension as it corners. For this reason, almost all cars today are fitted with anti-sway bars as standard equipment, although if they're not, kits make it easy to install the bars at any time.

ENGINE

Have you ever opened the hood of your car and wondered what was going on in there? A car engine can look like a big confusing jumble of metal, tubes and wires to the uninitiated.

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You can see in the figure that a device called a piston replaces the potato in the potato cannon. The piston is connected to the crankshaft by a connecting rod. As the crankshaft revolves, it has the effect of "resetting the cannon." Here's what happens as the engine goes through its cycle:

1. The piston starts at the top, the intake valve opens, and the piston moves down to let the engine take in a cylinder-full of air and gasoline. This Сis the intake stroke. Only the tiniest drop of gasoline needs to be mixed into

the air for this to work.

2. Then the piston moves back up to compress this fuel/air mixture.

Compression makes the explosion more powerful.

иNow the engine is ready for the next cycle, so it intakes another charge of air and gas.

3. When the piston reaches the top of its stroke, the spark plug emits a spark to ignite the gasoline. The gasoline charge in the cylinder explodes,

driving the piston down.

4. Once the piston hits the bottom of its stroke, the exhaust valve

starting withбАthe cylinders.

opens and the exhaust leaves the cylinder to go out the tailpipe.

Notice that the motion that comes out of an internal combustion engine

is rotational, while the motion produced by a potato cannon is linear (straight line). In an engine the linear motion of the pistons is converted into rotational motion by the crankshaft. The rotational motion is nice because we plan to turn (rotate) the car's wheels with it anyway.

Now let's look at all the parts that work together to make this happen, Д

Basic Engine Parts

The core of the engine is the cylinder, with the piston moving up and

down inside the cylinder. The engine described above has one cylinder. That

is typical of most lawn mowers, but most cars have more than one cylinder (four, six and eight cylinders are common). ИIn a multi-cylinder engine, the

cylinders usually are arranged in one of three ways: inline, V or flat (also known as horizontally opposed).

Different configurations have different advantages and disadvantages in terms of smoothness, manufacturing cost and shape characteristics. These advantages and disadvantages make them more suitable for certain vehicles.

Let's look at some key engine parts in more detail.

Spark plug The spark plug supplies the spark that ignites the air/fuel mixture so that combustion can occur. The spark must happen at just the right moment for things to work properly.

Valves The intake and exhaust valves open at the proper time to let in air and fuel and to let out exhaust. Note that both valves are closed during compression and combustion so that the combustion chamber is sealed.

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Piston A piston is a cylindrical piece of metal that moves up and down inside the cylinder.

Piston rings Piston rings provide a sliding seal between the outer edge of the piston and the inner edge of the cylinder. The rings serve two

where it would be burned and lost.

Most cars that "burn oil" and have to have a quart added every 1,000 miles are burning it because the engine is old and the rings no longer seal

и moves andбАthe crankshaft rotates.

things properly.

Connecting rod The connecting rod connects the piston to the crankshaft. It can rotate at both ends so that its angle can change as the piston

Crankshaft The crankshaft turns the piston's up and down motion into circular motion just like a crank on a jack-in-the-box does.

Sump The sump surrounds the crankshaft. It contains some amount of oil, which collects in the bottom of the sump (the oil pan).

ENGINE PROBLEMS

So you go out one morning and your engine will turn over but it won't start... What could be wrong? Now that you know how an engine works, you can understand the basic things that can keep an engine from running. Three fundamental things can happen: a bad fuel mix, lack of compression or lack of spark. Beyond that, thousands of minor things can create problems, but these are the "big three." Based on the simple engine we have been

Bad fuel mix - A bad fuel mix can occur in several ways:

You are out of gas, so the engine is getting air but no fuel.

The air intake might be clogged, so there is fuel but not enough air.

The fuel system might be supplying too much or too little fuel to the mix, meaning that combustion does not occur properly.

There might be an impurity in the fuel (like water in your gas tank) that makes the fuel not burn.

Lack of compression - If the charge of air and fuel cannot be compressed properly, the combustion process will not work like it should. Lack of compression might occur for these reasons:

Your piston rings are worn (allowing air/fuel to leak past the piston during compression). И

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The intake or exhaust valves are not sealing properly, again allowing a leak during compression.

There is a hole in the cylinder.

The most common "hole" in a cylinder occurs where the top of the

cylinder (holding the valves and spark plug and also known as the cylinder head) attaches to the cylinder itself. Generally, the cylinder and the cylinder Сhead bolt together with a thin gasket pressed between them to ensure a good

seal. If the gasket breaks down, small holes develop between the cylinder and the cylinder head, and these holes cause leaks.

Lack of spark - The spark might be nonexistent or weak for a number

of reasons:

If your spark plug or the wire leading to it is worn out, the spark will

be weak.

If the wire is cut or missing, or if the system that sends a spark down the wire is not working properly, there will be no spark.

the crankshaft cannot turn so the engine cannot run.

If the valves do not open and close at the right time or at all, air cannot get in and exhaust cannot get out, so the engine cannot run.

Here is a set of engine-related questions from readers and their answers:

What is the difference between a gasoline engine and a diesel engine? In a diesel engine, there is no spark plug. Instead, diesel fuel is injected into the cylinder, and the heat and pressure of the compression stroke cause the fuel to ignite. Diesel fuel has a higher energy density than gasoline, so a diesel engine gets better mileage.

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What is the difference between a two-stroke and a four-stroke engine? Most chain saws and boat motors use two-stroke engines. A twostroke engine has no moving valves and the spark plug fires each time the piston hits the top of its cycle. A hole in the lower part of the cylinder wall lets in gas and air. As the piston moves up it is compressed, the spark plug ignites combustion, and exhaust exits through another hole in the cylinder.

СYou have to mix oil into the gas in a two-stroke engine because the holes in

the cylinder wall prevent the use of rings to seal the combustion chamber. Generally, a two-stroke engine produces a lot of power for its size because there are twice as many combustion cycles occurring per rotation. However, a two-stroke engine uses more gasoline and burns lots of oil, so it is far more polluting.

иthe fuel. For example, a steam engine can use coal, newspaper or wood for the fuel, while an internal combustion engine needs pure, high-quality liquid or gaseous fuel.

You mentioned steam engines in this article -- are there any

advantages to steam engines and other external combustion engines? The

Wankel rotaryбАengines use the Otto cycle, but they do it in a very different way than four-stroke piston engines.Д

main advantage of a steam engine is that you can use anything that burns as

Are there any other cycles besides the Otto cycle used in car

engines? The two-stroke engine cycle is different, as is the diesel cycle

described above. The engine in the Mazda Millenia uses a modification of the

Otto cycle called the Miller cycle. Gas turbine engines use the Brayton cycle.

Why have eight cylinders in an engine? Why not have one big cylinder of the same displacement of the eight cylinders instead? There are a couple of reasons why a big 4.0-liter engine has eight half-liter

cylinders rather than one big 4-liter cylinder. The main reason is smoothness. A V-8 engine is much smoother becauseИit has eight evenly spaced

explosions instead of one big explosion. Another reason is starting torque. When you start a V-8 engine, you are only driving two cylinders (1 liter) through their compression strokes, but with one big cylinder you would have to compress 4 liters instead.

How are 4-cylinder and V6 engines different?

The number of cylinders that an engine contains is an important factor in the overall performance of the engine. Each cylinder contains a piston that pumps inside of it and those pistons connect to and turn the crankshaft. The more pistons there are pumping, the more combustive events are taking place during any given moment. That means that more power can be generated in less time.

4-Cylinder engines commonly come in “straight” or “inline” configurations while 6-cylinder engines are usually configured in the more

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compact “V” shape, and thus are referred to as V6 engines. V6 engines have been the engine of choice for American automakers because they’re powerful and quiet but still light and compact enough to fit into most car designs.

Historically, American auto consumers turned their noses up at 4- cylinder engines, believing them to be slow, weak, unbalanced and short on acceleration. However, when Japanese auto makers, such as Honda and СToyota, began installing highly-efficient 4-cylinder engines in their cars in the 1980s and 90s, Americans found a new appreciation for the compact engine. Even though Japanese models, such as the Toyota Camry, began quickly outselling comparable American models, U.S. automakers, believing иthat American drivers were more concerned with power and performance, continued to produce cars with V6 engines. Today, with rising gas prices and greater public environmental awareness, Detroit seems to be reevaluating the

4-cylinder engine for its fuel efficiency and lower emissions.

As бАfor the future of the V6, in recent years the disparity between 4- cylinder and V6 engines has lessened considerably. In order to keep up with the demand for high gas-mileage and lower emission levels, automakers have worked diligently to improve the overall performance of V6 engines. Many current V6 models come close to matching the gas-mileage and emissions standards of the smaller, 4-cylinder engines. So, with the performance and efficiency gaps between the two engines lessening, the decision to buy a 4- cylinder or V6 may just come down to cost. In models that are available with either type of engine, the 4-cylinder version can run up to $1000 cheaper than the V6. So, regardless of what kindДof performance you’re looking to get out of your car, the 4-cylinder will always be the budget buy.

One final note: It’s not a good idea to try to install a V6 engine into a car model that comes with a standard 4-cylinder. Retrofitting a 4-cylinder car to handle a V6 engine could cost more than simply buying a new car.

HOW FORMULA ONEИRACING

When the French held the first grand prix in 1906, the race organizers, the Automobile Club de France, couldn't have guessed how big their motor sport would become. That first race featured 32 cars on a 65-mile course near Le Mans and took two days to complete. The average speed of the winning car, a Renault driven by Hungarian Ferenc Szisz, was 62.887 mph.

From those humble origins, Formula One racing was born, and over the years, it has grown to be one of the most popular sports in the world. It appeals to millions of fans, attracts a huge sponsorship and delivers champions who are as revered as Olympic medalists. Why? Because Formula One racing satisfies our fundamental need to push technology to its limits and to enjoy, even if vicariously, the thrill and excitement of high-speed travel.

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This article will introduce you to the basics of Formula One. It will focus on all of the elements that make a grand prix race special, from the cars and drivers to the teams and tracks. And it will help you understand why Formula One has been described as "a saga of ecstasy and agony". The typical annual budget of a Formula One team can exceed $120 million.

Formula racing refers to a class of motor sport defined by openwheeled, single-seat race cars. Open-wheeled cars have their wheels outside

Сformula racing, featuring the best drivers in the most powerful, technically иadvanced cars. To be a champion in Formula One is to be the absolute best of the best - the No. 1 driver in the world. But no one jumps into a Formula One car on a whim and races to victory. Today's drivers compete for many years and across thousands of miles before they're ready for the ultimate test in the ultimate driving machine.

of the car's body, unlike "normal" cars and stock cars, whose wheels are under the fenders. As its name implies, Formula One is the pinnacle of

FormulaбАracing is, by definition, highly regulated. Specific rules – or formulas – define exactly how cars must be configured and exactly how a race must be run. Formula One rules come in two distinct categories. Sporting regulations cover all aspects of the race itself, from how a race is started to how it's concluded and everything in between. Technical regulations provide specific details about the car's major systems, including the engine, transmission and suspension. Throughout this article, we will be

Most Formula One drivers cut their teeth in other types of formula racing. In fact, the other categories of formula racing can be thought of as feeders to Formula One - proving grounds where a driver can develop his skills and, if he's good enough, earn a place on one of the 10 or so Formula One teams.

You might think having rulesДand regulations takes away some of the drama and excitement of Formula One racing, but in reality, it elevates the

looking at some of these rules more closely.

driver's skill to center stage. It also showcases the performance and efficiency of the cars themselves. It's no surprise that a Formula One season includes a championship for the manufacturers right alongside drivers, just as it's no

the Indianapolis 500. The Indy 500, however, is not associated with Formula One. It is the premier race event of the Indy Racing League (IRL), a predominantly American motor sport that includes the IndyCar Series and the Indy Pro Series. Another important class of open-wheel racing is the Champ Car World Series (formerly known as CART - Championship Auto Racing

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Teams), which features international drivers and tracks but is based largely in North America.

FORMULA ONE CARS

Fundamentally, Formula One cars are no different than the Chevy Сparked out in your garage. They use internal combustion engines and have transmissions, suspensions, wheels and brakes. But that's where the similarity ends. Formula One cars aren't designed for casual driving or cruising down the interstate. Everything about them is tweaked and tooled for one thing and one thing only - speed. Formula One cars can easily attain speeds of 200 mph - but during a race, the speeds are generally lower. During the 2006 Hungarian Grand Prix, the winner's average speed was 101.769 mph, and in

the 2006 Italian Grand Prix, it was 152.749 mph.

cars and aircraft, Formula One race cars feature monocoque construction. Monocoque is a French word meaning "single shell," which refers to the process of making the entire body out of a single piece of material. Once upon a time, that material was aluminum, but today it's a strong composite, like spun carbon fibers set in resin or carbon fiber layered over aluminum

mesh. The result is a lightweight car that can withstand the enormous downward-acting forces that areДproduced as the vehicle moves through the

The monocoque incorporates the cockpit, a strong, padded cell that

accommodates a single driver. Unlike the cockpits of road-ready cars, which

can show great variance, the cockpits of Formula One cars must adhere to very rigorous technical regulations. They must,Иfor example, meet minimum

size requirements and must have a flat floor. The seat, however, is made to fit a driver's precise measurements so his movement is limited as the car moves around the track.

Engine Before 2006, Formula One cars were powered by massive three-liter, V10 engines. Then the rules changed, specifying the use of 2.4- liter V8 engines. Even though power outputs fell with the rule change, Formula One engines can still produce nearly 900 horsepower. To put that into perspective, consider that a Volkswagen Jetta's 2.5-liter engine produces just 150 horsepower. Of course, the Jetta's engine is probably good for at least 100,000 miles or so. A Formula One engine needs to be rebuilt after about 500 miles. Why? Because generating all of that power requires that the engine run at very high revolution rates -- nearly 19,000 revolutions per

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