Wednesday, June 24, 2009

Confused About Car Technology? Read This



Stability Control: Mandatory in 2010, Do You Know What It Means?
by Hannah Elliott | Forbes.com

Motown Shutdown Car Makers Count On China Yes, New Auto Plants Will Be Built Hail The World's New Car King Do you know the difference between a supercharger and a turbocharger? Should you care?

Yes. A little auto expertise comes in handy when you want to impress your friends--or let a power-tripping mechanic know he can't jerk you around.

Here's our list of some of the most confusing car technologies and terms. From knowing your way around semi-automatic transmissions to understanding the difference between a mild hybrid and a dedicated hybrid, these factoids are essential knowledge for anyone who owns a car.

In Pictures: 10 Car Technology Terms Explained

Super Savers

President Obama's recent announcement about fuel efficiency and emissions standards has automakers talking about how turbochargers and diesel engines will lead the way to achieving a fleet-wide 35.5 mile-per-gallon requirement. But few people know just what makes turbochargers, or turbo-superchargers, as they're more accurately called, so essential to raw speed.

In short, turbochargers give cars extra guts. They use the engine's heat to compress ambient air and push it to the intake manifold. That additional oxygen enables the engine to take in more fuel, creating a combustive boost of power.

About one in four vehicles worldwide, including BMW's X6, Jaguar's XF and Porsche's 911 Turbo, use turbo-boost technology to achieve maximum power. By 2013, experts predict it will be closer to one in three.

David Paja, vice president of marketing for passenger vehicles at Honeywell, a manufacturer of automotive turbochargers, says they can be cost-effectively applied to hybrid, diesel and gasoline engines alike.

"It's a very natural technology tool to draw out fuel consumption in a transparent way for the customer, without any performance trade-off or reliability trade-off," Paja says.

He expects market penetration of turbo engines in the U.S. to grow from today's 6% to nearly 80% by the end of the next decade.

Switching Gears

Unlike the turbocharger, the proprietary names and multiple varieties of semi-automatic gearboxes can confuse even avid drivers. In general, semi-automatic gearboxes work like regular automatic transmissions, but they also have a mode that allows drivers to choose when to change gears, instead of letting the computer do it. For instance, with Porsche's patented tiptronic transmission, BMW's steptronic system or Aston Martin's touchtronic, drivers shift by bumping a knob near the stick shifter up or down, or by pushing a paddle on the steering wheel.

Porsche first introduced tiptronic technology in 1990 as an option in its 911. The technology has since become prevalent with brands like Audi, BMW, Chrysler, Honda and Nissan, although each make has registered it under a different name. This option appeals most to people who want a more engaging drive experience but don't want to be bothered with working a clutch.

Porsche also uses a similar doppelkupplung (German for double clutch), or PDK, technology. Audi's R8, BMW's M3, and Nissan's GT-R all use the system, as do several high-performance models in Europe.

The double-clutch transmission, a small, lightweight system that uses two internal clutches but no clutch pedal, was developed to win races on the track. It appeals to driving enthusiasts worldwide because of its incredible ease of speed and efficiency, says Porsche spokesman Dave Engleman.

It works by using electronic sensors to change gears, much like a standard automatic transmission. One clutch controls the odd gears, the other, the even gears. That duality means the driver can move a gear up or down without interrupting engine power, allowing seamless acceleration.

Safety Patrol

Safety features pose another threat to automotive know-how, and that confusion can lead to misuse or mistrust. For instance, professional drive instructors say many drivers often fail to take full advantage of the anti-lock braking system (ABS) in their car--or they mistake its signature rumble for a brake problem.

ABS works by preventing a vehicle's wheels from locking in the case of a slip. The most basic ABS uses speed sensors and hydraulics that monitor the speed of each wheel. When it detects that one wheel is turning either faster or slower than the others (which means the wheel is slipping or over-spinning), it reduces or increases brake force as needed. ABS adjusts continuously, which is why the brake pedal will rumble or pulse when the system is engaged.

The ABS system is a proven winner. It can decrease stopping distances on loose gravel by an average of 22%, according to the National Highway Safety Administration. A sister technology, electronic stability control (ESC), reduces the risk of single-vehicle crashes by about 35% for cars and dramatically more, 67%, for SUVs, according to the Insurance Institute for Highway Safety (IIHS).

ESC is more advanced than ABS. It works by sensing when a car might slip and then applying constant brake pressure to individual tires. David Zuby, senior vice president for vehicle research at IIHS, says the institute finds ESC so effective that it will not award its "top safety pick" distinction to any vehicle that does not offer it.

In Pictures: Car Technology Close Up

It's a comforting thought, especially once you understand the system. Now get out there and impress your friends with what you know.

Semi-Automatic Transmission

What it is: A type of automatic transmission that allows the driver to decide when to shift gears. Porsche was one of the earliest companies to offer this feature, its "tiptronic" transmission, on mainline-production cars in the U.S. BMW calls its half-manual transmission "steptronic"; Aston Martin calls it "touchtronic."

What it does: When this type of transmission is engaged, the driver decides when to shift, which he or she does by pushing the stick (or buttons on the steering wheel) either up or down, instead of letting the car do it automatically.

Cars that have it: Multiple models from Audi, BMW, Land Rover, Nissan, Porsche and Volkswagen, including the Audi A4, Land Rover Ranger Rover and Porsche 911.

Read on for more lists, rankings and autos coverage, including the cars you'll be driving in 2014 and why diesels aren't like they used to be.

Diesel Engine

What it is: A combustion engine that has no spark plugs and runs on diesel fuel.

What it does: Diesel engines compress air at twice the ratio of a gas engine and direct fuel straight into the combustion chamber, rather than using a throttle to regulate airflow. That makes for more power under low RPMs and a higher overall efficiency.

Cars that have it: Lots in Europe and some in the U.S., including the Audi Q7 TDI, BMW BMW X5 xDrive35d, Mercedes GL 320 BlueTec and Volkswagen Jetta TDI.

Read on for more lists, rankings and autos coverage, including the cars you'll be driving in 2014 and why diesels aren't like they used to be.

Turbocharger

What it is: A gas compressor that creates more engine power.

What it does: Turbochargers work by using heat from the engine to compress ambient air and push the denser air to the intake manifold. The additional oxygen makes it possible for the engine to accept more fuel, which translates into more power.

Cars that have it: Lots of them, and not just sports cars. Ford is pushing its new turbo technology for models like the Ford Flex, Lincoln MKX and Ford Taurus. Its "ecoboost" uses turbochargers that enable smaller engines to achieve the same power as larger variants, so a V6 acts like a V8.

Read on for more lists, rankings and autos coverage, including the cars you'll be driving in 2014 and why diesels aren't like they used to be.

Electronic Stability Control

What it is: A computerized system that stops cars from sliding out of control.

What it does: The system applies brake pressure to individual tires (rather than two or four at once) if it feels the car start to slip. It prevents over-steering and under-steering by stopping the outer front or inner rear wheel, respectively.

Cars that have it: Every new car made after model year 2009, as mandated by the U.S. government.

Read on for more lists, rankings and autos coverage, including the cars you'll be driving in 2014 and why diesels aren't like they used to be.

Mild Hybrid; Dedicated Hybrid

What it is: The term "mild hybrid" refers to a conventional vehicle that, thanks to a special starter, turns off when the car brakes, coasts or stops, and then seamlessly restarts. Mild hybrids get many of the benefits of a full hybrid but weigh less and cost less to implement. A "dedicated hybrid" is a car that was designed only as a hybrid (not one that was converted to a hybrid model after its conventional debut).

What it does: In a mild hybrid, the electric motor or generator operates at the same time as the engine and stores energy through regenerative braking and during stops and coasting. (Regenerative brakes store the energy generated by a car's movement rather than dissipating it as heat, like a conventional brake would.) Dedicated hybrids use both a gasoline engine and an electric or battery-powered motor but use them one after the other, not at the same time.

Cars that have it: The Saturn Vue Hybrid and Chevrolet Malibu use mild hybrid technology; the Toyota Prius and Honda Insight are dedicated hybrids.

Read on for more lists, rankings and autos coverage, including the cars you'll be driving in 2014 and why diesels aren't like they used to be.

ABS

What it is: The ABS, or anti-lock braking system, is a system that does just what it says. It prevents the wheels from locking during braking.

What it does: The most basic ABS uses speed sensors and hydraulics that monitor the speed of each wheel. When it detects that a wheel is turning either faster or slower than the others, it reduces or increases brake force as needed. ABS adjusts continuously, which is why drivers feel the brakes rumble or pulse when the system is engaged.

Cars that have it: More than two-thirds of all new vehicles manufactured worldwide.

Read on for more lists, rankings and autos coverage, including the cars you'll be driving in 2014 and why diesels aren't like they used to be.

Supercharger

What it is: A machine that compresses air in a forced-induction compression engine. The increased mass of air that a supercharger creates means more fuel can be provided to the engine, which creates more power. (A supercharger driven by the exhaust gasses from a turbine is called a turbo-supercharger, or turbocharger for short; simple superchargers, on the other hand, are driven directly mechanically by the engine's crankshaft).

What it does: Regular engines use pistons that move up and down to create a vacuum, which is then filled with air and combined with fuel to create combustion. Superchargers do the same without using a vacuum, which means they can force about 50% more air into the engine and create roughly 45% more horsepower and 30% more torque.

Cars that have it: The 2009 Jaguar XF, 2010 Audi S4 and any number of souped-up muscle cars.

Torque

What it is: Twisting force. When measured in foot-pounds, it’s the pounds of tug a rotating shaft delivers at a distance of one foot from its center. A gearbox can be used to change the torque coming out of an engine. When you downshift, you increase the torque and lower the RPMs delivered to the wheels. Diesel engines are known for their high levels of torque.

What it does: Torque is one of the two factors that determine the horsepower of an engine, the other being RPMs. To calculate hp, multiply torque in foot-pounds by rotating speed in RPMs, then divide by 5252.

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