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In automotive design, a Front Mid-engine, Front-wheel-drive layout (sometimes called FMF) is one in which the front road wheels are driven by an internal-combustion engine placed just behind them, in front of the passenger compartment. In contrast to the Front-engine, front-wheel-drive layout (FF), the center of mass of the engine is behind the front axle. This layout is typically chosen for its better weight distribution (the heaviest component is near the center of the car, lowering its moment of inertia). Since the differences between the FF and MF layouts are minor, most people consider the MF layout to be the same as the FF layout.
However, the mid-engined layout uses up central space, making the resulting vehicle rather long. This may be why no manufacturer currently offers the MF layout.
Examples of road cars using the MF layout include the Acura Vigor,[ citation needed ] Cord 810, BSA Scout, Citroën Traction Avant, Citroën DS, Renault 4 (and derivatives R5 and R6), Renault 16, Saab 900 Saab Sonett mk1, and the Citroën SM, also some commercial vehicles like the Tempo Matador. These vehicles have longitudinal mounted engines; transverse engined vehicles are possible in theory if the issue of passenger footwell location is addressed. The Toyota iQ comes close to this by having its front differential in front of the engine, [1] however despite this, the iQ is still considered to have an FF layout.
Traditionally, the term mid-engine has been reserved for cars that place the engine and transaxle behind the driver and in front of the rear axles [ citation needed ], as in the Lamborghini Countach or Ferrari Testarossa, but an engine placed in front of the driver's compartment but fully behind the front axle line also qualifies as mid-engine.
Minivan is a North American car classification for vehicles designed to transport passengers in the rear seating row(s), with reconfigurable seats in two or three rows. The equivalent classification in Europe is the M-segment, more commonly known as an MPV or a people carrier / mover. Minivans often have a 'one-box' or 'two-box' body configuration, a higher roof, a flat floor, a sliding door for rear passengers, and high H-point seating.
A hatchback is a car body configuration with a rear door that swings upward to provide access to a cargo area. Hatchbacks may feature fold-down second row seating, where the interior can be reconfigured to prioritize passenger or cargo volume. Hatchbacks may feature two- or three-box design.
Four-wheel drive, also called 4x4 or 4WD, refers to a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer case providing an additional output drive shaft and, in many instances, additional gear ranges.
Front-wheel drive (FWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel-drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel-drive and four-wheel drive vehicles.
quattro is the sub-brand used by the car brand Audi to indicate that all-wheel drive (AWD) technologies or systems are used on specific models of its Audi automobiles.
In automotive design, an FF, or front-engine, front-wheel-drive (FWD) layout places both the internal combustion engine and driven roadwheels at the front of the vehicle.
In automotive design, an RR, or rear-engine, rear-wheel-drive layout places both the engine and drive wheels at the rear of the vehicle. In contrast to the RMR layout, the center of mass of the engine is between the rear axle and the rear bumper. Although very common in transit buses and coaches due to the elimination of the drive shaft with low-floor buses, this layout has become increasingly rare in passenger cars.
In automotive design, an RMR, or rear mid-engine, rear-wheel-drive layout, is one in which the rear wheels are driven by an engine placed just in front of them, behind the passenger compartment. In contrast to the rear-engined RR layout, the center of mass of the engine is in front of the rear axle. This layout is typically chosen for its low moment of inertia and relatively favorable weight distribution. The layout has a tendency toward being heavier in the rear than the front, which allows for best balance to be achieved under braking. However, since there is little weight over the front wheels, under acceleration, the front of the car is prone to lift and cause understeer. Most rear-engine layouts have historically been used in smaller vehicles, because the weight of the engine at the rear has an adverse effect on a larger car's handling, making it 'tail-heavy'. It is felt that the low polar inertia is crucial in selection of this layout. The mid-engined layout also uses up central space, making it impractical for any but two-seater sports cars. However, some microvans use this layout, with a small, low engine beneath the loading area. This makes it possible to move the driver right to the front of the vehicle, thus increasing the loading area at the expense of slightly reduced load depth.
Economy car is a term mostly used in the United States for cars designed for low-cost purchase and operation. Typical economy cars are small, lightweight, and inexpensive to both produce and purchase. Stringent design constraints generally force economy car manufactures to be inventive. Many innovations in automobile design were originally developed for economy cars, such as the Ford Model T and the Austin Mini.
Rear-wheel drive (RWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the rear wheels only. Until the late 20th century, rear-wheel drive was the most common configuration for cars. Most rear-wheel drive vehicles feature a longitudinally-mounted engine at the front of the car.
A mid-engine layout describes the placement of an automobile engine in front of the rear-wheel axles, but behind the front axle.
Torsen Torque-Sensing is a type of limited-slip differential used in automobiles.
A transverse engine is an engine mounted in a vehicle so that the engine's crankshaft axis is perpendicular to the direction of travel. Many modern front-wheel drive vehicles use this engine mounting configuration. Most rear-wheel drive vehicles use a longitudinal engine configuration, where the engine's crankshaft axis is parallel with the direction of travel, except for some rear-mid engine vehicles, which use a transverse engine and transaxle mounted in the rear instead of the front. Despite typically being used in light vehicles, it is not restricted to such designs and has also been used on armoured fighting vehicles to save interior space.
Torque steer is the unintended influence of engine torque on the steering, especially in front-wheel-drive vehicles. For example, during heavy acceleration, the steering may pull to one side, which may be disturbing to the driver. The effect is manifested either as a tugging sensation in the steering wheel, or a veering of the vehicle from the intended path. Torque steer is directly related to differences in the forces in the contact patches of the left and right drive wheels. The effect becomes more evident when high torques are applied to the drive wheels either because of a high overall reduction ratio between the engine and wheels, high engine torque, or some combination of the two. Torque steer is distinct from steering kickback.
The configuration of a car body is typically determined by the layout of the engine, passenger and luggage compartments, which can be shared or separately articulated. A key design feature is the car's roof-supporting pillars, designated from front to rear of the car as A-pillar, B-pillar, C-pillar and D-pillar.
The layout of a motorised vehicle such as a car is often defined by the location of the engine and drive wheels.
A vehicle frame, also historically known as its chassis, is the main supporting structure of a motor vehicle to which all other components are attached, comparable to the skeleton of an organism.
In automotive design, an M4, or Mid-engine, Four-wheel-drive layout places the internal combustion engine in the middle of the vehicle, between both axles and drives all four road wheels.
France was a pioneer in the automotive industry and is the 11th-largest automobile manufacturer in the world by 2015 unit production and the third-largest in Europe. It had consistently been the 4th-largest from the end of World War II up to 2000.
The Citroën Traction Avant was a range of mostly 4-door saloons and executive cars, with four or six-cylinder engines, produced by the French manufacturer Citroën from 1934 to 1957. Approximately 760,000 units were produced.