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The technical terms in jargon we don't know.
The car dictionary from A to Z

Home road The technical terms in jargon we don't know.
The car dictionary from A to Z
The technical terms in jargon we don't know.
The car dictionary from A to Z
The technical terms in jargon we don't know. The car dictionary from A to Z

The world of engines can be really difficult to understand. It is quite frequent to have to deal with operations we are unfamiliar with, or with parts of the car we've never heard of!

So let's clarify and explore the car world jargon, from A to Z.

ABS
ABS is a braking assist system which uses solenoid valves to modulate the braking force and to ensure one wheel brakes rather than another. It is equipped with sensors that prevent the wheels locking during sudden braking, thereby avoiding the complete loss of wheel grip.

AERODYNAMICS
Aerodynamics are a part of mechanics that studies phenomena that occur as air moves and as bodies move within it. One of the most important parameters for a car is the CX coefficient measurement. This coefficient measures the car's ability to penetrate the air, a key factor in designing a car.

SPOILER
A spoiler is an aerodynamic element applied to the body of a car to increase its adherence when it reaches top speeds. The purpose of a spoiler is very similar to that of an airplane wing, the difference being that the spoiler is upside-down compared to a wing, so instead of raising the car it tends to squash it down towards the ground, giving it greater stability.

ANTIFREEZE
Antifreeze is a chemical compound containing ethylene glycol and anti-corrosion additives. The purpose of this compound is to prevent the engine cooling liquid from freezing in cold weather when very low temperatures are reached.

ANTI-SKID
This is an electronic device operated by the vehicle control unit, which prevents the wheels from skidding (caused by loss of grip on the ground).

AQUAPLANING
Aquaplaning is the loss of contact between the tyre and the road surface. This phenomenon is due to the fact that the side grooves of the tyre tread, due to particular conditions or to their configuration, are unable to eliminate all the water on the road surface when it rains continuously. Since all the water is unable to flow away, a thin layer of liquid forms between the tyre and the ground, making it near impossible to control the car.

TREAD
This is the part of a tyre that comes into contact with the road surface. The tread is extremely resistant to abrasion and it is notched with grooves. The thickness of these grooves must never fall below 1.6 mm. This is the minimum dimension envisaged to ensure full safety on the road and to avoid risking sanctions.

CAMBER ANGLE
The camber angle is the angle made by the wheels of a vehicle to determine the extent of its steering rigidity. To achieve this angle, the wheel rim plane is used as reference to form a right angle.

BELT                                                                                                                                     This is the short name given to the transmission belt: this element is shaped in a closed loop. The belt transmits motion from one element to another in the engine. There a various sizes of belts, each with a different function.

SPLIT DUAL BRAKE CIRCUIT
This safety system has been implemented on vehicles for quite some time. The system envisages the doubling of tubes in the braking system in strategic points. This doubling of tubes make it possible to brake the vehicle even if one of the circuits is malfunctioning.

ODOMETER
This device indicates the total and partial number of kilometres covered by the car. Usually this instrument is incorporated into the speedometer, forming a single instrument. The rev counter is activated by a flexible shaft which is operated by the gear box by means of a pinion gear.

TRACKING
Tracking, or toe, is an operation carried out on the wheels of a car to enhance its stability, driving safety and running comfort; it is usually performed every time the tyres are replaced or when you take your car in for servicing due to steering vibrations.

DECELERATION
This phenomenon is caused by using a device to counter the motion of a body. In cars, the component which allows most deceleration is the brake.

DIFFERENTIAL
This mechanism takes drive torque from a shaft and transfers it to the drive wheels. Applied to vehicles, it makes it possible to differentiate the revolution speeds of drive wheels on corners. There is also another type of differential: the self-locking differential. A self-locking differential is designed to balance the intensity of torque between two wheels when one of the two is slipping.

BRAKE DISC
A brake disc is a genuine disc, made of cast iron or carbon, which, combined with abrasive brake pads, are pushed by callipers which are activated by the brake circuit, slowing down or braking the vehicle motion entirely.

SPACERS
These discs are fitted on the wheels with nuts to increase the gauge of the car and improve its road holding.

BALANCING
This operation is used to eliminate any unbalancing of the car caused by worn tyres or by the stresses generated by the road surface. It is carried out by the tyre specialist in the workshop, using a dedicated machine to balance the wheels accurately, especially after the tyres have been fitted.

ESP
This is the acronym for Electronic Stability Control. ESP allows you to keep the stability of your car under control, adjusting the engine power and braking individual wheels at various intensities so as to re-stabilise the wheel configuration in case of skidding.

CLUTCH
This mechanism, activated using the first pedal on the left of your car, disconnects the engine shaft from the transmission to allow you to change gear and start from a standstill. The clutch can either be mechanical or electronic.

JOINT
A joint is a device used to create a link between two or more elements, such as the mechanical shaft or piping. In the case of the mechanical shaft, the joint joins two shafts, transmitting motion from one to the other.

INJECTOR
This part exploits the force of pressure to inject fuel into the cylinders and allow combustion to take place.

YAW
This is the rotation of the vehicle around a vertical axis that runs along the centre of gravity of the car. This phenomenon is the consequence of the centrifugal forces which are created on corners due to the different grip conditions between the rear axle and the front axle .

BRAKE FLUID
Brake systems on modern cars feature a hydraulic system. The driver, when braking, exercises a certain force onto the brake pedal. Depending on the intensity of this force, the vehicle slows down or brakes. This happens thanks to the brake fluid which, according to the principle of a hydraulic press, is transmitted to the braking parts.

LUBRICANT
Oily and highly viscous substance used to reduce friction between two moving parts. Its use inside an engine is essential to ensure a much longer life for mechanical parts which are subject to particularly significant wear.

CYLINDER BLOCK
The cylinder block comprises all the cylinders and the engine shaft, including all the fittings used to anchor it to the vehicle chassis. Latest-generation models are made of aluminium, to decrease the weight and improve cooling in petrol engines, whereas diesel engine cylinder blocks are made of compacted graphite iron.

PILLARS
The pillars are parts of the car body on which the roof of the vehicle rests. They are particularly important owing to the structural robustness of the upper part of the vehicle and the resistance to crushing if the car overturns. They are therefore the parts which keep the living space of the passenger compartment intact.

MULTIGRADE OILS
The differences between oils are determined by their viscosity. In the past, depending on the atmospheric pressure, the oil had to be changed to operate in winter or summer temperatures. Multigrade oils are products which can be used in any season.

HOMOKINETIC JOINT
A homokinetic or CV (constant-velocity) joint allows a drive shaft to transmit power through a variable angle, at constant rotational speed, without an appreciable increase in friction or play.

PANIC STOP
This is the technical name given to sudden braking in an emergency manoeuvre. In this case, the brake pedal is pushed all the way down. In cars that are not fitted with ABS, the wheels are locked completely with the ensuing loss of grip, whereas in cars featuring ABS the braking is distributed evenly, allowing grip on the ground to be maintained.

WHEELBASE
This is the distance between the front axle and the rear one. The wheelbase is measured between the centre of the wheels on the same axle. This measurement is important when you need to determine the road handling of the vehicle.

PAD
The pad is part of the brake. It is also called a friction lining. It is a metallic part of the brake which allows friction to be created on the disc, causing the vehicle to slow down.

BRAKE CALLIPERS
These callipers are activated by pressure in the braking system; pistons exert pressure on the callipers, allowing them to affect the brake pad and cause friction on the disc, and therefore reduce the speed of the vehicle.

FOUR-WHEEL DRIVE
This technology is only featured on certain types of vehicle, and it allows all four wheels to steer. Thanks to this technology, more accurate and precise driving trajectories can be set.

ROLLING RESISTANCE
This force is opposite to the force of motion which interferes with the rolling of the tyre. Due to the layout of weights in our car, the tyre warps on contact with the ground. This warping of the tyre leads to energy losses which affect the regular motion of the car. Good rolling resistance makes for energy savings and lower fuel consumption levels. In addition, depending on the grooves in the side of the tyre, the rolling resistance causes less or more noise in the tyre.

ROLL BAR
This consist of steel bars placed above the passengers' heads in a sports car or cabriolet. This system of bars makes it possible to protect people if the vehicle is overturned.

SUV
This is the acronym for Sports Utility Vehicle. It means a capacious sports or work vehicle.

SPEEDOMETER
This is one of the instruments on the dashboard designed to measure the speed of motion in a unit and it is expressed in revolutions per minute. This instrument allows us to read the speed of our vehicle, and it is expressed in kilometres per hour. In the past, this instrument was mechanically linked to the drive shaft; these days, instead, cars are fitted with another device with electric pulses, which vary depending on the speed and are transformed into kilometres per hour.

TUBULAR CHASSIS
This is the load-bearing frame of a vehicle. This is the chassis of the car which is created by welding together tubes which are subsequently covered with panels, to make up the car body.

ROAD HOLDING
Road holding means the vehicle's ability to maintain the trajectory set by the driver. Road holding is determined and affected by multiple factors, such as the vehicle ride, aerodynamics, the quality and the condition of the tyres and their pressure.

THIRD BRAKE LIGHT
This brake light is fitted inside the rear windscreen. It supplements the other two brake lights fitted in the rear light clusters. Today, unlike in the past, the third brake light has become to all intents and purposes a legal obligation.

TRANSMISSION
This includes all the parts of an engine whose task is to transfer the force generated by the engine to the drive wheels.

SAFETY GLASS
Safety glass is made by joining two glass panes measuring 2.5 mm in thickness. A layer of Polyvinyl butyral, approximately 0.5 mm thick, is placed between these two panes of glass. This type of safety glass makes it possible to protect people in the event of impact, it withstands break-in attempts, it limits the damage caused by noise pollution and it protects against ultraviolet rays.

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