Terminology Explained – Turbocharger
No12: Turbocharger
Pull quote: “General figures would indicate that a turbocharged engine gives a further 35 percent increase in power over a naturally-aspirated engine”
It’s something we’ve all heard of, some of us used, and most find themselves unable to afford the insurance ramifications. A turbocharger is widely known as an application beneath the bonnet that greatly increases a cars performance, but just how exactly does it work?
A bit of history first folks: In 1905 the first Turbocharger ever made was invented by a Swiss born engineer under the name of Alfred Buchi. Buchi applied the turbocharger initially to diesel ships in the early 1920′s, which then eventually made its debut to the automotive industry shortly after.
For those who don’t know, engines operate on an air/fuel mixture basis, breathing air in and using fuel to create energy; in turn running the engine and its internal parts that operate the driveshaft and wheels.
A turbocharger operates by drawing in an increased amount of air, at a much faster rate allowing a quicker air/fuel mixture ratio. A turbo powered car may be recognisable by a badge placed to the rear boot, for example a TDI (Turbo Diesel Injection) or newly introduced TSI (Twincharger Supercharged Injection) from VW.
Now over to the tech spec side of things, non-mechanically minded people look away! Inside the turbocharger are a compressor and turbine linked together by a shared axis. The turbine inlet receives exhaust gases through the engine exhaust manifold, allowing the turbine wheel to turn around. With the turbine now turning, this then drives the compressor, compressing ambient air and sending it straight to the air intake of the engine. With the air compressed, this allows for the engine to take in a far greater amount of air than normal, thus meaning that with more air added, more fuel can be used too.
It’s said that most turbochargers take in 50 percent more air over a standard engine. The typical boost made by a turbo is in around 6 to 8 pounds per square inch. General figures would indicate that a turbocharged engine gives a further 35 percent increase in power over a naturally-aspirated engine, which in lehmans terms means greatly improved performance!
Turbochargers in recent years have become a feature associated only to larger high performance cars, however in 2006 Volkswagen stepped to fore by unveiling the all new Golf 1.4TSI engine. Despite being small capacity with a mere 1400cc’s, these impressive new engines can blast out in excess of 165bhp, however not only is the TSI engine turbocharged, but supercharged too! The engine has been fitted to the new Golf GT and Sport, boasting performance of 0-100kph in less than 8 seconds. And for the cost conscious among you, its extremely fuel friendly too, doing well in advance of 38MPG! The innovative TSI engine technology is now available in the Golf GT and Sport along with the Golf Plus, Touran SE and Jetta.
Changes in the Mercedes 300E Class From 1991-1995
In 1990, Mercedes Benz put out their mid sized line up. It was made up of a 300CE coupe, a 260E, 300E four door sedan and a four door station wagon 300TE. The 260E sedan employed a 158-horsepower, 2.6 liter, 6-cylinder engine. The 300CE coupe got a face lift with a 217-horsepower, 2.0 liter inline six with dual camshafts. The rest of the models received single camshafts and 3.0 liter inline sixes that were rated at 177-horsepower.
The 250D sedan received a turbocharged 5-cylinder diesel engine, which was available in the spring of 1990. The 300E sedan and the 300TE wagon both received automatic 4-wheel drive. Along with previous upgrades, all models received new fuel injection systems. Along with the fuel injection, the models received a driver side airbag with a passenger side airbag as an optional addition. The anti-lock breaking system was universal across the models.
In 1991, the Mercedes Benz E class received two upgrades. Mercedes’ “traction control system” was available as an option in the rear wheel drive 300E sedan, the 300CE coupe and the 300TE wagon. The diesel 300, with a 2.5 Turbo could also be upgraded to ASD, which is an automatic locking differential.
The 1992 Mercedes Benz E class picked up two models that had V8 engines. The 4.2 liter V8 in the 400E was boosted to 268 horsepower with this upgrade. The limited edition 500E was appropriated also with a 5.0 liter V8, that was also used in the 500SL. In the 400E and 500E, the passenger side airbag was standard. On other models, the passenger side airbag was optional.
Nineteen ninety three gave rise to a convertible and two new engines. The new Mercedes E class now had a 300D 2.5 Turbo, a 300E 2.8 sedan with a new 2.8-liter twin-cam engine, a 300E sedan, a 300CE coupe, a 300TE wagon and 3.2-liter 6-cylinder engine Cabriolet 300CE. The V8′s of the lineup was a 400E and a 500E with all models now having standard driver and passenger side airbags.
The restyling of models in 1994 came with new grilles, hoods, headlights, assembles, trunk lids and tail lamps. The E320 came in all four body types. The E420 and the E520 both has V8 engines. Made as an early 1995 model, a 300D sedan was produced in the spring of 1994 with a 134-horsepower 3.0 liter diesel, 6 cylinder engine.
Mercedes E-Class 2009 Review
Last year, Mercedes introduced a new C-class Which is the nearest it has come to making a MW 3- series. The C-class has the spirit and driving dynamics that its predecessors lacked and even introduced different front-end styling to distinguish the most popular Sport versions. Surely, its bigger brother, the new model E-class, would follow the same pattern?
The answer is no. The new E class has many virtues, but sportiness isn’t one of them. At least not for the first versions to go on sale; we can expect the E63 AMG, announced at the New York Auto Show in April and due to go on sale at the end of the year, to be the exception.
Mercedes bosses say that as the heart of the range, the E-class is too important to change fundamentally. They point out that in this market sector, Mercedes is dominant; it easily out-sells the BMW 5 Series and Audi A6. So the ninth generation would develop by evolution, not revolution. It had to be a comfortable familiarity but below the surface incorporate a myriad of detail improvements and all the latest technology.
So W212 is lower, wider and more prominently wedge-shaped than its predecessor. That allows it to have the best aerodynamics in its class: a drag coefficient of 0.25 (most of its rivals are 0.28 or above) The imposing grille is still there – and the star still rises above it – but the four headlamps are angular rather than oval.
To meet European regulations for pedestrian safety, that low, wind-cheating bonnet has to be able to pop up 50mm in an accident; while others use complex pyrotechnics, Mercedes has an elegantly simple solution with steel springs.
The emphasis on aerodynamics is part of a program to improve fuel consumption and carbon dioxide emissions dictated by other EC regulations. For some reason, in Germany environmental measures that elsewhere are called ‘green’, turn blue.
Mercedes calls its eco-pack age BlueEfficiency. It includes more efficient engines, low rolling resistance tyres and energy-saving alternators, and fuel, air conditioning and power steering pumps that switch off when not required.
The four-cylinder petrol engines are downsized to 1.8 litres, have direct fuel injection and are turbocharged. The three four-cylinder CDI diesels – E200, E220 and E250 – all use the new 2.1-litre engine in different states of tune. The E350 CDI and E350 CGI have developments of the previous six-cylinder engines; the petrol CGI also has direct injection. The 5.5-litre V8 engine for the top model, the E500, is carried over from the old E-class; this is the only version not to have the additional BlueEfficiency features.
In Europe, more than half the market for this type of car is diesel, so I concentrated on the E250 CDI and E350 CDI. These engines develop respectively 204 and 231bhp. The 250 comes equipped with a six-speed manual or five-speed automatic transmission while the six-cylinder 350 has Mercedes’ latest seven-speed automatic.
The four-cylinder diesel has a curious combination of characteristics. It is unusually smooth and quiet at idle but noisy when pushed hard. Although the 250 has two turbochargers in sequence to even out the power delivery, the performance is far from startling, and the automatic transmission does it no favours. In this respect, the seven-speed E350 CDI is much lively but our experience with the new Jaguar AJ-V6D (and the BMW 335d) suggests it is not the best of the latest crop of high performance diesels.
As before, the F-class is better to travel in than to drive. All models have adaptive shock absorbers that react to the driving situation and adjust to provide maximum ride comfort or cornering stability as required. The seats are improved, the air conditioning allows the choice of three different air volume and distribution modes and is arranged in three independent zones driver, front passenger and rear passengers – and there is more space inside thanks to the 2cm longer wheelbase and 3.5cm extra width. Mercedes aimed to make this car the most comfortable car in its class. I think it may have succeeded.
Mercedes has been in the fore front with most of the active safety systems that we now take for granted: ABS anti-lock braking, ASR traction control, ESP stability control. The new F-class moves this to a new level with a raft of ‘assist’ systems, all electronic and very clever and designed to see and react to the motoring hazards and mitigate their consequences. This car doesn’t quite drive itself but you get the impression that it could… Where to start? Attention Assist is a good example of Mercedes-knows- best. This drowsiness detector is standard equipment on all E-class models. Sensors monitor 70 different parameters to pick up irregularities in driving behavior. If it detects a series of steering errors or other inconsistencies it concludes that the driver is sleepy and sounds a warning and a symbol representing a cup of tea appears on the instrument display to suggest that you take a break.
Brake Assist Plus is a radar- based system linked to the optional Distronic cruise control which provides the driver with optimum braking pressure when a collision is imminent and if no action is taken will apply the brakes automatically. Lane Keeping Assist uses a camera on the windscreen to follow lines in the road and when the car has moved out of a lane with out indicating, an electric motor in the steering wheel vibrates its rim as a warning. Blind Spot Assist provides a light warning of the presence of a car in the blind spot of the side mirror. Speed Limit Assist, recently available on a number of other cars, recognizes speed limit signs and displays the prevailing limit at the center of the speedometer.
Nightview Assist Plus uses an infrared camera to give a greyscale image on the dashboard screen to show hazards beyond the light range and highlight pedestrians. The new E-class takes vehicle lighting further forward, liter ally and technologically. Others have active headlamps that turn with steering or illuminate corners but Mercedes’ optional Adaptive Highbeam Assist uses a windscreen camera to recognize oncoming traffic and adjust the headlamp beams accordingly. This is much more than automatic dip ping; it changes the shape of the dipped light beam to give the best possible road illumination from 65 to as much as 300 meters. It works beautifully.
Mercedes talks of all these systems making the car your ‘intelligent partner’. My first reaction was ‘too much stuff’ but there is no doubt that they represent further advances in safety technology and of course you don’t have to tick all the options boxes.