Monday, June 8, 2009

Confused about car technology? Read this

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 (6.6 L/100km)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 per cent to nearly 80 per cent 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.

Electronic stability control (ESC), reduces the risk of single-vehicle crashes by about 35 per cent for cars and dramatically more, 67 per cent, for SUVs

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 per cent, according to the National Highway Safety Administration. A sister technology, electronic stability control (ESC), reduces the risk of single-vehicle crashes by about 35 per cent for cars and dramatically more, 67 per cent, 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.

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

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