Saturday, March 12, 2011

A Short Course on Automobile Engines

Internal combustion gasoline engines run on a mixture of gasoline and air. The ideal mixture is 14.7 parts of air to one part of gasoline (by weight.) Since gas weighs much more than air, we are talking about a whole lot of air and a tiny bit of gas. One part of gas that is completely vaporized into 14.7 parts of air can produce tremendous power when ignited inside an engine.

Let's see how the modern engine uses that energy to make the wheels turn.

Air enters the engine through the air cleaner and proceeds to the throttle plate. You control the amount of air that passes through the throttle plate and into the engine with the gas pedal. It is then distributed through a series of passages called the intake manifold, to each cylinder. At some point after the air cleaner, depending on the engine, fuel is added to the air-stream by either a fuel injection system or, in older vehicles, by the carburetor.

Once the fuel is vaporized into the air stream, the mixture is drawn into each cylinder as that cylinder begins its intake stroke. When the piston reaches the bottom of the cylinder, the intake valve closes and the piston begins moving up in the cylinder compressing the charge. When the piston reaches the top, the spark plug ignites the fuel-air mixture causing a powerful expansion of the gas, which pushes the piston back down with great force against the crankshaft, just like a bicycle rider pushing against the pedals to make the bike go.

Let's take a closer look at this process.

Engine Types

The majority of engines in motor vehicles today are four-stroke, spark-ignition internal combustion engines. The exceptions like the diesel and rotary engines will not be covered in this article.

Typical Cylinder ArrangementsThere are several engine types which are identified by the number of cylinders and the way the cylinders are laid out. Motor vehicles will have from 3 to 12 cylinders which are arranged in the engine block in several configurations. The most popular of them are shown on the left. In-line engines have their cylinders arranged in a row. 3, 4, 5 and 6 cylinder engines commonly use this arrangement. The "V" arrangement uses two banks of cylinders side-by-side and is commonly used in V-6, V-8, V-10 and V-12 configurations. Flat engines use two opposing banks of cylinders and are less common than the other two designs. They are used in engines from Subaru and Porsche in 4 and 6 cylinder arrangements as well as in the old VW beetles with 4 cylinders. Flat engines are also used in some Ferraris with 12 cylinders

Most engine blocks are made of cast iron or cast aluminum..Piston and Connecting Rod

Each cylinder contains a piston that travels up and down inside the cylinder bore. All the pistons in the engine are connected through individual connecting rods to a common crankshaft.

CrankshaftThe crankshaft is located below the cylinders on an in-line engine, at the base of the V on a V-type engine and between the cylinder banks on a flat engine. As the pistons move up and down, they turn the crankshaft just like your legs pump up and down to turn the crank that is connected to the pedals of a bicycle.
Typical Cylinder HeadA cylinder head is bolted to the top of each bank of cylinders to seal the individual cylinders and contain the combustion process that takes place inside the cylinder. Most cylinder heads are made of cast aluminum or cast iron. The cylinder head contains at least one intake valve and one exhaust valve for each cylinder. This allows the air-fuel mixture to enter the cylinder and the burned exhaust gas to exit the cylinder. Engines have at least two valves per cylinder, one intake valve and one exhaust valve. Many newer engines are using multiple intake and exhaust valves per cylinder for increased engine power and efficiency. These engines are sometimes named for the number of valves that they have such as "24 Valve V6" which indicates a V-6 engine with four valves per cylinder. Modern engine designs can use anywhere from 2 to 5 valves per cylinder.

CamshaftThe valves are opened and closed by means of a camshaft. A camshaft is a rotating shaft that has individual lobes for each valve. The lobe is a "bump" on one side of the shaft that pushes against a valve lifter moving it up and down. When the lobe pushes against the lifter, the lifter in turn pushes the valve open. When the lobe rotates away from the lifter, the valve is closed by a spring that is attached to the valve. A common configuration is to have one camshaft located in the engine block with the lifters connecting to the valves through a series of linkages. The camshaft must be synchronized with the crankshaft so that the camshaft makes one revolution for every two revolutions of the crankshaft. In most engines, this is done by a "Timing Chain" (similar to a bicycle chain) that connects the camshaft with the crankshaft. Newer engines have the camshaft located in the cylinder head directly over the valves. This design is more efficient but it is more costly to manufacture and requires multiple camshafts on Flat and V-type engines. It also requires much longer timing chains or timing belts which are prone to wear. Some engines have two camshafts on each head, one for the intake valves and one for the exhaust valves. These engines are called Double Overhead Camshaft (D.O.H.C.) Engines while the other type is called Single Overhead Camshaft (S.O.H.C.) Engines. Engines with the camshaft in the block are called Overhead Valve (O.H.V) Engines.

Now when you see "DOHC 24 Valve V6", you'll know what it means.

How an Engine Works

Since the same process occurs in each cylinder, we will take a look at one cylinder to see how the four stroke process works.

The four strokes are Intake, Compression, Power and Exhaust. The piston travels down on the Intake stroke, up on the Compression stroke, down on the Power stroke and up on the Exhaust stroke. Running Engine

  • Intake
    As the piston starts down on the Intake stroke, the intake valve opens and the fuel-air mixture is drawn into the cylinder (similar to drawing back the plunger on a hypodermic needle to allow fluid to be drawn into the chamber.)
    When the piston reaches the bottom of the intake stroke, the intake valve closes, trapping the air-fuel mixture in the cylinder.
  • Compression
    The piston moves up and compresses the trapped air fuel mixture that was brought in by the intake stroke. The amount that the mixture is compressed is determined by the compression ratio of the engine. The compression ratio on the average engine is in the range of 8:1 to 10:1.
    This means that when the piston reaches the top of the cylinder, the air-fuel mixture is squeezed to about one tenth of its original volume.
  • Power
    The spark plug fires, igniting the compressed air-fuel mixture which produces a powerful expansion of the vapor. The combustion process pushes the piston down the cylinder with great force turning the crankshaft to provide the power to propel the vehicle. Each piston fires at a different time, determined by the engine firing order. By the time the crankshaft completes two revolutions, each cylinder in the engine will have gone through one power stroke.
  • Exhaust
    With the piston at the bottom of the cylinder, the exhaust valve opens to allow the burned exhaust gas to be expelled to the exhaust system. Since the cylinder contains so much pressure, when the valve opens, the gas is expelled with a violent force (that is why a vehicle without a muffler sounds so loud.) The piston travels up to the top of the cylinder pushing all the exhaust out before closing the exhaust valve in preparation for starting the four stroke process over again.

Oiling System

Oil is the life-blood of the engine. An engine running without oil will last about as long as a human without blood. Oil is pumped under pressure to all the moving parts of the engine by an oil pump. The oil pump is mounted at the bottom of the engine in the oil pan and is connected by a gear to either the crankshaft or the camshaft. This way, when the engine is turning, the oil pump is pumping. There is an oil pressure sensor near the oil pump that monitors pressure and sends this information to a warning light or a gauge on the dashboard. When you turn the ignition key on, but before you start the car, the oil light should light, indicating that there is no oil pressure yet, but also letting you know that the warning system is working. As soon as you start cranking the engine to start it, the light should go out indicating that there is oil pressure.

Engine Cooling

Internal combustion engines must maintain a stable operating temperature, not too hot and not too cold. With the massive amounts of heat that is generated from the combustion process, if the engine did not have a method for cooling itself, it would quickly self-destruct. Major engine parts can warp causing oil and water leaks and the oil will boil and become useless.

While some engines are air-cooled, the vast majority of engines are liquid cooled. The water pump circulates coolant throughout the engine, hitting the hot areas around the cylinders and heads and then sends the hot coolant to the radiator to be cooled off. For more information on the cooling system, visit our online club.

Engine Balance

Flywheel A 4 cylinder engine produces a power stroke every half crankshaft revolution, an 8 cylinder, every quarter revolution. This means that a V8 will be smother running than a 4. To keep the combustion pulses from generating a vibration, a flywheel is attached to the back of the crankshaft. The flywheel is a disk that is about 12 to 15 inches in diameter. On a standard transmission car, the flywheel is a heavy iron disk that doubles as part of the clutch system. On automatic equipped vehicles, the flywheel is a stamped steel plate that mounts the heavy torque converter. The flywheel uses inertia to smooth out the normal engine pulses.

Balance Shaft Some engines have an inherent rocking motion that produces an annoying vibration while running. To combat this, engineers employ one or more balance shafts. A balance shaft is a heavy shaft that runs through the engine parallel to the crankshaft. This shaft has large weights that, while spinning, offset the rocking motion of the engine by creating an opposite rocking motion of their own.

Wednesday, March 9, 2011

Future Car Technology

Future Car Pictures

Future Car Pictures

Future Car Pictures

Future Car Engine

Future car technology will most likely involve a whole host of choices in regard to the fuel of choice.

Right now many automakers are gearing up for offering vehicles that are able to run on ethanol or other biofuels (such as biodiesel), which is the path of least resistance for the near future.

But, what about longer term? In the longer term, future car technology will most likely involve cars that run on hydrogen, electricity, air, nitrogen or even nuclear power. Some may see the nuclear-powered car as the most far-fetched of all of the ideas, but this is a mistake.

In fact, in 1958 the first nuclear automobile was pioneered and called the Ford Nucleon. The Ford Nucleon was a concept vehicle that was supposed to be powered by a small nuclear reactor at the rear of the vehicle fueled by radioactive material. No working prototypes were ever built, however.

So, this is not the say that nuclear-powered cars will never be part of the future. Car technology will most likely advance to the state will this will one day be a likely fuel of choice.

But, what is here now? Hydrogen, electricity, air and nitrogen cars all have had working prototypes built. In fact, in regard to electric vehicles, production models have also been built. But, the range of electric cars and their recharging rate have always been their downfall.

So, this is where hydrogen cars step in. Hydrogen cars at this writing can run from either internal combustion engines or fuel cells. Some of the current models of hydrogen cars like the GM Sequel have a proven driving range of over 300 miles in real world conditions. The BMW Hydrogen 7 has rolled out as a lease vehicle and is a dual fuel vehicle that can run off either liquid hydrogen or gasoline.

The Honda FCX was the first hydrogen car to be offered as a lease in 2004 and now the second lessee, actress Q'orianka Kilcher who played Pocahontas in the movie "The New World".

Electric cars also offer an option in regard to future car technology if the aforementioned issues may be resolved. Companies like Tesla, Zap and Phoenix Motorcars are making headway in developing these vehicles for the marketplace.

And, then there is the MDI air cars which may be going over big in Europe and India once the compressed air infrastructure is in place. The MDI air cars also have an onboard compressor that plugs into any outlet so this will help with vehicle acceptance.

So, far their has only been one nitrogen car prototype of note and this is the CooLN2Car developed by the University of North Texas. The car has stalled in development, however, due to lack of research funds.

Two other parts of advanced car technology to note are the future flying cars that will be taking flight over the next two or three years and smart cars that will also be seeing the highways and byways sometime in the future as well.

BMW Mini Rocketman in Geneva Motor Show 2011

One more awesome electric vehicle made by BMW. The Mini Rocketman is one stylist invention from BMW which is going to unveil in the Geneva Motor Show. This is a foot shorter than original mini with three-door hatchback. The Rocketman is 3.4 meter long which can accommodate a driver with two passanger and a fourth adult on the short journey.

This car features lighter carbon frame and its fuel consumption is 33 kilometers per liter. It contains leather interior and wrap-around light strip. This three-cylinder Rocketman features large headlights, chrome grille trim and trapezoidal rear lights with wrap around windows are crapped with a transparent glass roof.

Tuesday, March 8, 2011

Nissan Esflow at Geneva Motor Show

Nissan released one of its superfast electric models in the Geneva Motor Show. This is one purely electric concept embedded with rear wheels. The automobile Informedly uses dual 80-kW (107-hp / 109-PS) motors to propel a appurtenance to 100 km/h in underneath 5 seconds which puts in on par the top most sport car in the market.

After the super Nissan creation which contains innovative electric vehicle with lithium-ion batteries, now the creation of Nissan Esflow is now. Resembling a 370Z, though with some-more radical lighting and additional sculpting, a new Nissan ESFLOW judgment will tarry on guard via a Geneva Show.

Monday, March 7, 2011

Kickboxer Concept-Use Diesel Engine and All Wheel Drive

Motor exotic concept was actually introduced in 2009. The designer is Ian McElroy, who dreamed of this bike will use a turbo boxer engine. Kitchen pacunya taken from the legendary rally cars, Subaru WRX.

But it seems the trend lately of diesel a year makes McElroy redesign this motor. Using a diesel engine with an additional drive drinkers all-wheel drive.
The engine is of course taken from the Subaru as well. While the successor of power to the front and rear wheels using a chain. Uniquely,
Kickboxer Concept uses the front suspension as Vyrus M2. But more sophisticated because the pro-style arm.

But how beloknya yes if the front drive chain power Kickboxer use the router? Yamaha also had a motorcycle with all-wheel drive system.
But the difference is using a hydraulic Yamaha is more flexible than the chains. Design is too crazy maybe, but still. Interesting!

2012 Mercedes-Benz SLK-Class Roadster

2012 Mercedes-Benz SLK-Class Roadster
For the first time Mercedes-Benz is offering a choice of three variants of the lightweight-construction vario-roof for the new SLK: in just a few seconds this feature transforms the roadster into a coupe with a “fixed” roof at the touch of a button – and vice versa: The standard version is a roof painted in the vehicle color. Optionally available is a panorama vario-roof with dark-tinted glass. The third option is a world premiere – the panorama vario-roof with MAGIC SKY CONTROL. This glass roof switches to light or dark at the press of a button. In light mode it is virtually transparent, offering an open-air experience even in cold weather. In its dark state the roof provides welcome shade and prevents the interior from heating up from the sun’s rays. In other words: a comfortable atmosphere at the touch of a button.

Infiniti Etherea Concept at Geneva Motor Show 2011

In this 81st Geneva Motor Show, Infiniti is going to launch its more flexible model to the show named as Etherea Concept. It contains a hybrid powertrain that contains 245horsepower and 2.5liter four-cylinder engine.

This Etherea can be said as one new model luxury model. This Etherea is designed in Japan and this is more coupe that a hatchback in inspiration.

According to Francois Bancon “ETHEREA represents a redefinition, not a revolution – a car for buyers whose idea of luxury is very different from the stereotypes. ETHEREA is not a stereotype.   It is a little bit borderline. It is an expression of identity and personality.  It adds new values, as well as conveying existing ones. “More than anything, it is not just another luxury compact car.”

Sunday, March 6, 2011

Yamaha V-Max

Latest Info yamaha Vmax that makes people stare to see it. Yamaha recently introduced its collaboration with world renowned fashion brand, Hermes. This cooperation is manifested into the V-Max.
For you fans still remember the movie Ghost Rider with Nicholas Cage major star who told me about the devil eradication of evil. In this film Johnny Blaze (Cage) is always riding a motorcycle and in the sequel film there new ride Yamaha Vmax.

Specification of Yamaha V-Max:
1679cc, Liquid-cooled, 4-stroke, DOHC, 4-valve, V-4
Bore x Stroke
90.0 x 66.0 mm
Compression Ratio
Fuel Management
Fuel Tank Capacity
15.0 L
Final Transmission
Shaft drive
5-speed w/ slipper clutch
Length 2395 mm
Width 820 mm
Height 1190 mm
Seat Height 775 mm
Wheelbase 1700 mm
Ground Clearance 140 mm
Wet Weight 310 kg with 15.0 litres of fuel
Frame Type
Aluminium diamond
Suspension Front
52mm Telescopic fork, 120mm travel
Suspension Rear
Swingarm, link-type, fully adjustable, 110mm travel
Brakes Front
320mm dual wave discs, six pot radial mounted calipers
Brakes Rear
298mm single wave disc
Tyres Front
Bridgestone radial 120/70 R18MC(59V)
Tyres Rear
200/50 R18MC(76V)

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