2011 Audi A1

2011 Audi A1 Side View

As luxury automakers focus more on how to extend their brand into smaller packages that maintain the prestige and performance of their larger models, Audi has a few advantages.

2011 Audi A1 Rear Side View

Its new 2011 Audi A1 subcompact hatchback can draw on the full experience of its parent, Volkswagen Group, while selling for much more money than the 2011 Volkswagen Polo that's roughly the same size.

2011 Audi A1 Photo

We don't know for sure that the 2011 Audi A1 is headed for the States, but it will debut in March at the 2010 Geneva Motor Show. Audi has already released an official teaser and announced that singer Justin Timberlake will star in an Internet campaign for the 2011 A1 next spring.

2011 Audi A1 Front View

2011 Audi A1 Best Interior

2011 Jaguar XF S First Look

2011 Jaguar XF S Photo

While we are all well aware of just how great of an automobile that the Jaguar XFR really is, the luxury car builder has announced details about an upcoming alternatively fueled model of the XF sport sedan for 2011 that brings the same high performance attitude and upscale amenities of the top of the line version into a new diesel burning four door dubbed the XF S.

2011 Jaguar XF S Interior

The XF S is powered by a 275 HP diesel mill that promises not to disappoint drivers thanks to the Jag’s Adaptive Dynamics system, a unit that is currently featured on the XFR and XK that constantly adjusts the suspension to improve handling without giving up an ounce of comfort. The result improves on the XF’s already impressive handling and strikes a clever balance between a luxury ride and sports car agility, which will be an option on the high performance diesel.

2011 Jaguar XF S Exotic Car

The exterior of the new Jaguar XF S can be upgraded with a new aerodynamics package similar to the XFR’s which includes black mesh grill inserts, horizontal blades across the lower air intakes and bolder side skirts. Meanwhile the interior features upscale touches like high gloss Piano Black veneer and a Jet Suedecloth headliner that is available as an option on Premium Luxury and Portfolio Diesel S models; ensuring that you don’t have to give up style and luxury just to be green.

2011 Jaguar XF S Car Wallpaper

2011 Lotus Elise Pictures

2011 Lotus Elise Super Car

The Lotus Elise revolutionised the sportscar market 14 years ago when the small lightweight agile 2-seat mid engine sportscar was introduced. By ensuring that the Elise stuck rigidly to Lotus' core values of performance through light weight, the Elise was able to produce supercar performance with city car economy.

2011 Lotus Elise Rear Angle View

Making its debut at the 80th International Geneva Motorshow, the 2011 model year Lotus Elise introduces a number of changes and improvements to maintain its class leading position.

2011 Lotus Elise Front View

Diesel Engine Combustion Efficiency

Index Key: ENG048
Author: gerald j ballmann
Subject: Diesel engine combustion efficiency.
1) What limits the compression ratio of a diesel engine?
2) What is the best fuel to use in a diesel engine for maximum efficiency?

Response #: 1 of 2
Author: daniel n koury jr
The compression ratio for a particular engine is limited by how strong the
engine block is. Too much pressure (compression) and something will break.
The best fuel will also depend on the design of the engine. But as a
general rule, the greater the energy content of the fuel, the greater the
efficiency (at least in terms of miles per gallon or km per liter). Water
has a low energy content and would not make a good fuel for example.

Response #: 2 of 2
Author: david r munoz
The limits to compression ratio are based on the knock limits of the fuel.
Knock is the term used to describe the auto ignition that occurs when a fuel
ignites because the pressure in the cylinder is such that combustion occurs.
In a spark ignited engine, it is best if the spark control the ignition,
since timing of the piston motion with the motion of the flame front is
critical to the operation of an efficient engine.
In a diesel engine, one relies on auto ignition of the fuel because the
engine is basically compression ignited (there is no spark plug). There-


fore, we want the fuel to be autoignited. However, some types of combustion
waves move faster than others. There are waves called detonation waves that
contribute to sonic velocities of the hot gases in the cylinder. It is
generally, the nonuniformity of the pressure within the cylinder that are
responsible for knock. Some believe that these nonuniformities are due to
detonation and others believe they are due simply to nonuniform combustion
or auto ignition in the cylinder.
The knock limits for a fuel are determined on a special single cylinder
engine called a CFR engine. On this engine, the compression ration can be
gradually changed. In general, a fuel is burned in the engine and the
compression ratio is changed high and low until the engine begins to shake.
This is known as the knock limit for the fuel. The higher the knock limit,
the higher the compression ratio.

How Diesel Engines work

Diesel Engine is a type of internal combustion engine (one from which work is obtained by compression of the fuel within the cylinders themselves) which operates on the constant pressure or diesel cycle principle. Fuel is admitted directly into the cylinder and combustion takes place as a result of the heat of compression.
In these engines, gas pressure in the cylinder acts on the piston, forcing it down during the power stroke to drive the crankshaft through connecting rods. The extreme positions reached by the piston correspond to the top and bottom dead center positions (TDC & BDC) of the crank and are so designated. The inside diameter of the cylinder is the bore. The distance traveled between dead centers (TDC &BDC) is the stroke, corresponding volume is the swept volume, or displacement, of the cylinder. The cylinder volume above piston when piston is at TDC is called clearance volume. Similarly the cylinder volume above piston when piston is at BDC is called cylinder volume. The ratio of the cylinder volume to the clearance volume is the nominal compression ratio.
The greater combustion pressure is the result of the higher compression ratio used by diesel engines. Compression ratio is a measure of how much the engine compresses the air inside the cylinder. In a diesel engine compression ratio ranges from 14:1to as high as 24:1 are commonly used. Higher compression ratios are possible because only air is compressed, and then the fuel is injected. This is one of the factors that allows the diesel engine to be so efficient.

Fuel Injector Testing

Mount he fuel injector in its test rig and connect up the oil supply. Under no circumstances should hands be placed under the injector spray. The high velocity oil jet can penetrate the skin and cause blood poisoning. With the injector priming valve open, operate the hand pump to prime the injector. Once the fuel flows from the priming valve it can be closed.

1. Oil Container

2. Pressure Gauge

3. Shut off valve

4. Pump lever

5. Test pump

6. Injector

7. High Pressure fuel pump

Operate the pump rapidly for several strokes. The injector should open with a high pitched chatter and fuel should be emitted in a fine cloud. After the injector opens, check to make sure the pressure does not fall off too quickly.

To test for the tightness between the nozzle needle and seat, operate the hand pump slowly to gradually increase the pressure until it is just below opening pressure. Maintain the pressure for a few seconds and ensure injector is not dripping.

To test for tightness between needle and guide, operate the hand pump to increase pressure until it is just below opening pressure. See how long it takes the pressure to fall off. If the pressure falls quickly the needle and guide should be replaced.

Where nozzles are cooled internally, these spaces should be pressure tested to check for tightness. Blank off one of the fuel valve cooling connections and fill the injector cooling space with water or fuel, depending upon the cooling medium. Then connect a low pressure air supply to the other connection. Leave the air on for a short period of time and test for internal or external leakage.

Measure Indicated Power in Diesel Engine with Indicator Diagram

The burning of fuel in an engine cylinder (2 stroke or 4 stroke diesel engine) will result in the production of power at an output shaft, some of the power produced in the cylinder will be used to drive the rotating masses of the engine.

Typical indicator diagram for a 2 stroke engine is shown in figure below. The area within the diagram represents the work done within the cylinder in one cycle.
The area can be measured by an instrument known as 'Planimeter' or by the use of the mid ordinates rule. [On modern engines this diagram can be continuously taken by employing two transducers, one pressure transducer in the combustion space and other transducer on the shaft. Through the computer we can thus get on line indicated diagram and power of all cylinders.]

The area is then divided by the length of the diagram in order to obtain mean height. This mean height, when multiplied by the spring scale of the indicator mechanism, gives the indicated mean effective pressures for the cylinder. The mean effective or average pressure [Pm] can now be used to determine the workdone in the cylinder.

Calculations

Area of the indicator diagram = a [mm²]

Average height of the diagram = a [mm²] / l [mm]

Average mean indicator pressure = a [mm²] / l [mm] x k [bar / mm]

or P_m = ( a / l ) x k [bar]

where k = spring scale in bar per mm

Work done in one cycle = Mean Indicated Pressure x Area of the Piston x Length of stroke

= [P_m] x [A] x [L]

To obtain the power of this unit, it is necessary to determine the rate at which work is done,

i.e. multiply work by number of power strokes in one second.

Now, Indicated Power of Unit [i_p] =

Mean Indicated Pressure [P_m] x Area of Piston [A] x Length of Stroke [L] x Number of Power Strokes per Second [N]

or

Indicated Power of Unit = Pm L A N

2010 Aston Martin Rapide Car

2010 Aston Martin Rapide Photo

Aston Martins have always unapologetically been about grand touring. Some car magazine somewhere has always managed to dog Astons for not being as sharply tuned as Ferraris or Porsches for harrowing all-out attacks on mountain passes.

2010 Aston Martin Rapide New Edition

Be it a 1963 DB5 or an '09 DBS, these iconic British cars have put a priority on getting their passengers to their destinations in comfort, quickly and in grand style.

2010 Aston Martin Rapide Interior

Well, they did for two people, anyway. Passengers three and four (if there were seats at all for them) would have to be 4 years old, without legs and/or very flexible. Enter the 2010 Aston Martin Rapide, a car that adds a pair of doors to the brand's grand touring tradition and successful DB9 platform.

2010 Aston Martin Rapide Exotic Car

Oh, there have been four-door Aston Martins before, but those Lagonda models were so bizarre, so atypical of the brand and ultimately so unpopular that you'd be just as likely to see Sasquatch cruising along on the freeway in a Smart Fortwo. The Rapide, on the other hand, won't be confused for anything but an Aston Martin.

2010 Aston Martin Rapide Car Wallpaper

The Rapide looks like a stretched DB9 with an extra set of doors and two adult-sized seats. That's essentially what it is. Under the skin is Aston's bonded aluminum chassis and rear-mounted transmission shared with every other car in the line. However, the Rapide has 9.7 additional inches of wheelbase, is a full foot longer and is 10 inches wider. It actually has a bigger footprint than the much bigger-looking Porsche Panamera, yet it weighs slightly less (4,299 pounds versus the Porsche's 4,343).

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2011 Volkswagen Polo GTI

2011 Volkswagen Polo V GTI Side View

While the official debut will not be made until March at the Geneva Motor Show, Volkswagen has revealed today the first images of the Polo GTI sporty hatchback. It will go on sale early this summer in both three and five-doors versions.

2011 Volkswagen Polo V GTI Rear Angle View

The Polo GTI is powered by a 1.4-liter TSI gasoline engine with turbo- and supercharging developing a total of 180 hp and a peak torque 184 lb-ft of torque, available from 2,000 to 4,500 rpm.

2011 Volkswagen Polo V GTI Interior

The engine is mated to a 7-speed DSG dual-clutch transmission. The car sprints from 0 to 60 mph in 6,9 seconds and can hit a top speed of 142 mph.

2011 Volkswagen Polo V GTI Image

Compared to a standard Polo, the GTI version has been lowered by 15 mm and comes with more rigid suspension. The exterior is defined by blacked out headlamps with LED daytime running lights, twin tail pipes, a GTI honeycomb grille with a red frame and of course 17" alloy wheels.

2011 Volkswagen Polo V GTI Front Angle View

The Polo GTI is back. A powerful 132 kW / 180 PS comeback! ThisThe Polo GTI is back. A powerful 132 kW / 180 PS comeback! This GTI lives up to its legendary name: Superior handling properties unified with uncompromising engine dynamics and a maximum of safety.

2011 Volkswagen Polo V GTI Steering Wheel
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2011 Citroen DS3 R

2011 Citroen DS3 R Sport Car Series

Citroen will unveil the hatchback version of the 2010 Citroen DS3-R in the month of March during the Geneva Motor Show. The R version of the DS3 will be limited to just 1000 units, and according to the company said, the model is notable for its strikingly sporty character in its equipment and the use of carbon fiber.

2011 Citroen DS3 R Side View

As for engines, the 2010 Citroen DS3-R model has an engine that is based on the THP petrol, 1.6-liter that generates 150 hp, but that was amended by Citroën which generates 200 hp.

2011 Citroen DS3 R Rear Angle View

Furthermore, the model has a retouched suspension and chassis modified to improve performance. The 2010 Citroen DS3-R also has a carbon finish in the front bumper, on the skirts of the chassis and the flaps that cover the wheels, which have some 18 "wheels.

2011 Citroen DS3 R Picture

To complete the exterior look, the 2010 Citroen DS3-R model also has a diffuser made of carbon fiber. The exclusivity of the model is evident in the colors to be revealed at the Geneva Motor Show. On the inside, the model also has elements of carbon, as shown on the instrument panel and steering wheel, door armrests and the supports of the upper instrument panel.

2011 Citroen DS3 R Interior


2011 Citroen DS3 R Front Angle View


2011 Citroen DS3 R First Look


2011 Citroen DS3 R

2011 Maserati Granturismo

2011 Maserati Granturismo Luxury Car

The GranTurismo is a grand-touring sports car, selling as much on exclusivity, personal luxury, and performance and competing directly with the Aston Martin V8 Vantage, Porsche 911, and Ferrari California.

2011 Maserati Granturismo Gauges View

The GranTurismo is also related to the Maserati Quattroporte and the Alfa Romeo 8C Competizione.

2011 Maserati Granturismo Exotic Sport Car

For 2007, the Maserati GranTurismo replaced the Maserati Coupé, and it offers as much performance as its predecessor with more refinement. You can see the close resemblance between the GranTurismo coupe and the Quattroporte sedan, but any similarities end there; the GranTurismo has an attractive sports-coupe silhouette, in a design that you might expect of an Italian exotic. Up close, the low front end and the flared rear fenders in particular make its profile a thing of beauty.

2011 Maserati Granturismo Convertible Side View

A 405-horsepower, 4.2-liter V-8 is standard on the GranTurismo, but GranTurismo S models get a 433-hp, 4.7-liter version. GranTurismo models can get to 60 mph in 5.1 seconds and to a top speed of 177 mph, while the GranTurismo S (offered from 2008 on) takes just 4.5 seconds and can reach 183. In both cases, the engine lives up to its Ferrari pedigree, emitting a low rumble at idle and a tuneful wail under full acceleration.

2011 Maserati Granturismo Convertible Rear View

The Maserati GranTurismo feels snug, because of its quite narrow footwells and tight sport seats, but it's also warm and inviting thanks to soft leather and excellent trims.

2011 Maserati Granturismo Convertible Interior

There are back perches in the GranTurismo, but they're not functional even for kids and have nearly no headroom. In front, the GranTurismo has enough space for taller adults, and trunk space should be just enough for a weekend trip. Maserati sells most of its GranTurismo and Quattroporte models by order, with a long list of customization options, interior trims, and luxury features.

2011 Maserati Granturismo Convertible Front View


2011 Maserati Granturismo Convertible First Look


2011 Maserati Granturismo Convertible Car Picture


2011 Maserati Granturismo Convertible Car Photo

2011 Porsche Cayenne

2011 Porsche Cayenne Side View

Porsche has officially unveiled its 2011 Cayenne SUV at the 2010 Geneva Motor Show. Although the Cayenne is widely known as a performance vehicle, the German automaker had fuel-efficient hybrid and diesel version of the 2011 Cayenne on display.

2011 Porsche Cayenne Rear View

The exterior of the new Cayenne follows in Porsche’s philosophy of evolutionary design, but the 2011 model does feature a much sleeker appearance than the current Cayenne, thanks to more organic body lines.

2011 Porsche Cayenne Front View

With a redesigned interior, following Panamera cues, the 2011 Cayenne sports a new and longer center console and a repositioned shift-knob. Overall, nearly everything has been freshened and tweaked, including placement of the center air vents, sportier gauges and a new steering wheel.

2011 Porsche Cayenne First Look

The 2011 boast five separate trim levels with gas, diesel and hybrid drivetrains. The Cayenne range starts out in base Cayenne form, featuring a 300 horsepower 3.6L V6. One step up in the Cayenne S, packing the Panamera’s 400 horsepower 4.8-liter V8 engine. The Cayenne Turbo sits atop the Cayenne hierarchy, receiving its power via a 500 horsepower twin-turbocharged 4.8L V8.

2011 Porsche Cayenne Car Wallpaper

Power for the Cayenne S Hybrid comes from Audi’s supercharged 3.0-liter V6 producing 333-horsepower, connected to a three-phase synchronous electric motor which receives power from a 38 kW NiMH battery that resides in the spare tire well. The electric motor adds another 47 horsepower.

2011 Porsche Cayenne Car Picture


2011 Porsche Cayenne Car Interior