Australian Car Advice | News Blog

HSV GTS with Magnetic Ride Control suspension (MRC)

“An outstanding innovation, which dramatically improves ride, handling and safety”

HSV’s GTS accelerates from O-100km/h in less than five seconds. For that reason alone, it belongs to an elite club.

Even more exclusive, is its membership in the MRC club, whose members include the latest Chevy Corvette (an option on the Vette) and Ferrari’s super expensive 599 Fiorano.

Turbocharger

A Turbocharger is a small compressor driven by the engine’s exhaust gases which increases power. Unlike a supercharger which is driven by a belt off the engine to increase power. A Turbocharger is used to increase the power output of a car by increasing the mass of oxygen entering the engine - essentially by cramming more air into the engine, more fuel can burn and hence more power can be given per cycle.

The biggest advantage of turbochargers is their considerable low weight and cost and given the excellent performance increase they are used widely. However aftermarket turbo kits can cause damange to a vehicles engine depending on the setup.

An alternative to the turbocharger and the supercharger is to use a multivalve engine, where more valves than the traditional two per cylinder move air and fuel through the engine more quickly. Nevertheless performance cars have multivalves AND turbochargers.

MacPherson struts

A modern front suspension system which supports the car’s weight and acts as shock absorbers. The main alternative is a double wishbone arrangement. McPherson Struts consists of a small subframe (or a substantial link stabilized by a secondary link) which allows a mounting point for the axle of the wheel. Generally the McPherson Strut is only used for the front wheels, but it also used for rear wheels in some cars.

Limited slip differential (LSD)

LSD is a mechanical version of traction control, limiting wheel spin on an axle in two and four-wheel drives. We can notice the main advantage of a LSD when it is compared to a typical standard differential. Imagine a scenario whereby in the case of the standard differential one wheel has no contact with the ground. In this scenario, the contacting wheel will remain stationary, and the non-contacting wheel will rotate at nearly twice its intended velocity! Therefore the torque transmitted will be zero and the vehicle will remain stationary.

This sort of situation is rather rare in everyday driving, but in more extreme situations such as in motor sports or in off-road driving this situation is highly undesirable and does occur. Using an LSD limits the velocity difference between the two wheels and allows for torque to be transmitted correctly given that some friction is available on at least one of the driving wheels.

Low profile tyres

Low profile tyres have excellent grip on dry roads but are stiffer than ordinary tyres and therefore provide a firmer ride. These tyres have a greater width ratio to cope with the demands of higher performance vehicles. “Profile” refers to the height of the sidewall compared with the width of the tread, expressed as a percentage. A number of 60 or lower is considered low profile.

Disadvantages are:

• Much more road noise
• A stiffer ride, far harder than conventional tyres
• Less resistance to aquaplaning due to the amount of rubber on the road
• Price

The key advantages of low profile tyres are:

• Better handling and grip
• Far superior traction and braking power compared to ordinary tyres
• Looks

Ultra-low profile tyres (tyres with a number below 50) generally require a higher inflation pressure than taller profile tyres. This is due to Ultra-low profile tyres having a smaller internal volume and hence in order to carry the same load, these tyres require more pressure. However a problem that arises due to this is that lack of pressure can cause serious damage to tyres and is usually not obvious to the driver as the car still tends to behave normally evne if the tyre is inflated or even flat. Once the tyre has been damaged due to inflation it is usually irreparable.

Foglamp Foglights

An auxiliary headlamp mounted low on the front of a car (often on the bumper) for use in fog. Casts a broad, flat beam on the left-hand kerb. Sometimes the fog lamps can in different colours. For example the old Nissan Silva (S13) used a yellow beam. Alternative coloured fog lamps can be rather annoying for other motorists on the road.

Disc brakes

Disc brakes - unlike drum brakes,use a calliper that grips the disc rotor to the wheel to gain friction. They tend to create more heat than drum brakes, but is designed to continue operating effectively in these conditions - and they are also exposed to outside air which helps with cooling. Within the caliper are usually two brake pads, one for either side of the rotor. These pads clamp together when the brake pedal is pressed. This is a similar concept to that of drum brakes but it is far superior not only in performance but also for reliability.

Problems with Disc Brakes

Many things can happen to disc brakes. But the more common problems are warping (caused by extreme heat), scarring (occurs when pads are not changed when due), and cracking (a bit rare - but occurs due to uneven rotor expansion). The easiest way to repair these problems is by machining the discs. However by doing so, you are effectively reducing the life of your brakes and it might just be cheaper just to replace instead of actually spending money on repairs.

Bash plate

The protector plate fitted underneath vital components like your car’s engine, transmission and fuel tank. The Bash plate is generally made from thick steel. The Idea of the bash plate is to take the hard knocks that you might hit on the road.

Anti-lock braking System (ABS)

Anti-lock braking system prevents your car’s brakes from “locking up” and skidding. When the brake pedal is hit with force, short sharp pulsations are felt as the car’s computer system applies and release braking effort. A typical ABS is composed of a central electronic unit (CEU), four speed sensors covering all wheels, and two or more hydraulic valves connected to the brake circuit. The CEU continiously monitors the rotation speed of each wheel to determine if wheels are going to lockup. It can detect this by sensing wheels which are rotating considerably slower than the others. Once it has detected a possible lockup - the CEU moves the valves to help relieve the pressure within the braking circuit, by doing so it helps to reduce the braking force on the targetted wheel. Following that the wheel then turns faster and when it starts turning too fast, the force is reapplied. The ABS system does the prococess repeatedly.

Problems with ABS

The sensors on the wheels might get contaminated by metallic dust. When this condition occurs the sensors become less efficient in picking up problems. In modern ABS systems, two more sensors are added to help:

• wheel angle sensor,
• gyroscopic sensor

The idea behind this is that when the gyroscopic sensor detects that the car’s direction is not the same as what the wheel sensor reports, the ABS software will cut in to brake the necessary wheel in order to help the car go the direction the driver intends.

For more information on how ABS works, click here

Windshield

Modern windshields are generally made of laminated safety glass, which consists of two curved sheets of glass with a plastic layer laminated between them for safety, and are glued into the window frame. Earlier windshields were made of toughened glass and were fitted in the frame using a rubber or neoprene seal.

Windshields protect the vehicle’s occupants from wind, temperature extremes, and flying debris such as dust, insects, and rocks. Properly installed automobile windshields are also essential to safety; along with the roof of the car, they provide protection in the case of a roll-over accident in the vehicle.

Windshield Wipers

Most cars have an intermittent wiper system, which permits the driver to select a delayed wipe that operates only every few seconds. A representative wiper/washer unit is the wiper assembly, which incorporates a depressed park system that places the wiper blades below the hood line in the parked position. The relay control uses a relay coil, relay armature, and switch assembly. It controls starting and stopping of the wiper through a latching mechanism. An electric washer pump is mounted on the gear box section of the wiper. The wiper unit gear assembly drives it.

Windshield Washers

All cars use an electric pump-operated windshield washer with a positive displacement washer pump. On some, the motor is placed in the washer reservoir, while on others, it is driven by a wiper motor. When the pump is attached to the wiper motor, the four lobe cam starts a spring-loaded follower, but the pump does not operate all the time that the wiper motor is running. This is because the pumping mechanism is locked out and pumping action occurs.