|
Term
|
Definition
|
| 4WD | Four wheel drive. All four wheels are directly driven from the engine. |
| ABS | Anti-lock braking system. ABS repeatedly releases and applies the brakes, in a fraction of a second, to prevent wheels from locking and keep the car in control. |
| Active safety | Safety features which involve active vehicle response to avoid accidents (usually through sensors), e.g. ABS or ESP. |
| Airbag | Air-filled bag that helps prevent head and upper-body injuries during severe collisions. Front airbags are deployed from the steering wheel and the instrument panel. Side airbags are deployed from the door and curtain airbags drop from the roof. |
| Automatic gear box | Automatic transmissions that upshift and downshift gears without requiring the driver to engage the clutch. |
| Birdview | Nissan navigation system. Using 3D graphics, Birdview simulates the view of the route ahead from the viewpoint of a hovering bird. |
| Body Type | The type of vehicle as determined by the shape or style of its body, e.g. sports car, off-road vehicle, etc. |
| Bore x Stroke | In an engine, the relation between the diameter of the cylinder bore and the length of the stroke of the piston. This measurement tells you if the engine is designed to deliver more speed or more torque. A long-stroke engine (where the length of the piston stroke is greater than the diameter of the bore of a cylinder) delivers more torque at the expense of maximum power; while a short-stroke engine delivers more engine power with less low-end torque. |
| Chassis | The frame that supports the body, engine, drivetrain and suspension components of a vehicle. |
| Clutch | A drivetrain component that connects an engine to a manual transmission and is used to disengage the transmission from the engine in order to change gears. The driver pushes the clutch pedal to shift gears. |
| CO2 emission | The amount of carbon dioxide fumes produced by a vehicle. CO2 is a pollutant. |
| Coil springs | A spring made from wire that has been wound into a spiral shape. Coil springs are used in the suspension of many vehicles |
| Common Rail | A diesel direct fuel-injection system that maintains constant pressure throughout the fuel line. The engine's electronics regulate the injection pressure and timing according to engine speed and load. |
| Crawl ratio | Crawl ratio is calculated by multiplying transmission gears, transfer case (in 4Lo) and axle differentials.
The lower the crawl ratio is, the slower a vehicle can “crawl” in first gear and low range. Low crawl ratios mean higher torque available at the wheels, good for climbing steep gradients.
|
| CVT gear box | Continuously Variable Transmission. The transmission ratio changes progressively and not in step like a manual gearbox. This system uses a metallic V belt. Nissan uses a V roller. |
| Differential | Transmission part located between the gearbox and wheels. The differential allows a speed difference between left and right wheels or between front and rear axles to avoid wheels scrubbing. |
| Direct injection | Engine system where petrol or diesel is injected directly into the engine cylinder instead of in a pre-combustion chamber or manifold. Direct injection provides more efficient combustion with lower consumption and gas emissions. |
| Disc brake | A braking system where a calliper forces a pair of brake pad against the disc rotor in each wheel, stopping the vehicle. |
| Drum brake | A braking system where a hydraulic cylinder forces a pair of brake shoes against the inner surface of the brake drum, which is a metal cylinder, in order to stop the vehicle. |
| EDB | Electronic Brakeforce Distribution: Function integrated to some ABS systems to distribute the brake force in an optimal way between the front and the rear wheels, whatever the load or the pressure on the brake pedal. |
| EGR (Exhaust Gas Recirculation) | The EGR system collects one part of the exhaust gas and diverts them back to the engine via the intake manifold. It reduces the amount of oxygen used in the combustion process and thus also reduces temperature peak and nitrogen oxide emission. |
| ESP | Electronic Stability Program. ESP automatically stabilises the vehicle in dangerous driving situations by applying brake pressure to each wheel individually and reducing engine torque if necessary. It uses many sensors to measure the turning speed of the wheels, the steering angle and the rotation of the vehicle around the vertical axis. |
| Fuel cell | Power system prototype. The fuel cell generates electric power by combining oxygen and hydrogen. Its only waste product is water steam. |
| Fuel injection | Fuel injection delivers fuel under pressure into an engine's combustion chamber. |
