Front-Wheel Drive (FWD) layouts.

Click para leer versión en español

The XF GTI, with a FF layout, can perform a front-wheel spin, stopping the rear wheel with the hand brake or e-brake.

FWD overview:

  • Front-Wheel Drive (FWD):

Front drivers burnout

This car is doing a front wheel burnout, due to the FWD layout.


Front-wheel drive (FWD) is a form of engine/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.

FF means “Front engine, Front-Wheel Drive”.

In automotive design, an FF, or Front-engine, Front-wheel-drive layout places both the internal combustion engine and driven roadwheels at the front of the vehicle.

This type of layout has suffered important changes through time;

Historical arrangements

Early cars using the FF layout include the 1929 Cord L-29, 1931 DKW F1, the 1948 Citroën 2CV, 1949 Saab 92 and the 1959 Mini. In the 1980s, the traction and packaging advantages of this layout caused many compact and mid-sized vehicles to adopt it.

There are four different arrangements for this basic layout, depending on the location of the engine, which is the heaviest component of the drivetrain.

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Mid-engine / Front-wheel drive

R4 1987 1

Mid-engine, front-wheel drive (MF layout): Renault 4 mid-engine, front-wheel-drive layout allows greater distance between front doors and wheelwells, and short front overhang.

Automotive diagrams 07 En

The earliest such arrangement was not technically FF, but rather mid-engine, front-wheel-drive layout (MF). The engine was mounted longitudinally (fore-and-aft, or north-south) behind the wheels, with the transmission ahead of the engine and differential at the very front of the car. With the engine so far back, the weight distribution of such cars as the Cord L-29 was not ideal; the driven wheels did not carry a large enough proportion of weight for good traction and handling. The 1934 Citroën Traction Avant solved the weight distribution issue by placing the transmission at the front of the car with the differential between it and the engine. Combined with the car’s low slung unibody design, this resulted in handling which was remarkable for the era. Citroën and Renault used this layout in some models into the 1980s.

Renault 5 First generation with 5 doors in Spai

The Renault 5 was one of the last successful mid-engine, front-wheel-drive layouts.

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Front-engine longitudinally mounted / Front-wheel drive

Automotive diagrams 08 En

AutoUnion (DKW) 1000 (registered 1965) right

Longitudinally front-mounted engine, front-wheel drive (FF longitudinal layout): The Auto Union 1000, (today Audi) longitudinal layout superseded the DKW F89 front transverse engines in the 1950s.

The 1946 Panhard Dyna X, designed by Jean-Albert Grégoire, had the engine longitudinally in front of the front wheels, with the transmission behind the engine and the differential at the rear of the assembly. This arrangement, used by Panhard until 1967, potentially had a weight distribution problem analogous to that of the Cord L29 mentioned above. However, the Panhard’s engine was very light, reducing the effect. The engine of the Citroën 2CV was in front of the front wheels, with the transmission behind the axle and the differential between the two. This became quite popular; cars using this layout included the German Ford Taunus 12M and the Lancia Flavia and Fulvia. This is the standard configuration of Audi and Subaru front wheel drive vehicles. The first generation Oldsmobile Toronado and the Saab 99 and “classic” Saab 900 had their engines mounted approximately on the front axle center line, with power being taken by chains or a gear train to a transmission and differential mounted below and beside the engine.

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Front-engine transversely mounted / Front-wheel drive

Automotive diagrams 10 En

Fiat 128 Rally 1972

Transverse front-mounted engine, front-wheel drive (FF transverse layout): Fiat 128, followed the footsteps of the Autobianchi Primula

Issigonis‘s Mini of 1959 and related cars such as the Maxi, Austin 1100/1300 and Allegro had the engine transversely mounted. The transmission was located in the sump below the crankshaft, with power transmitted by transfer gears. The 1955 Suzuki Suzulight also introduced a front engine with a transversely installed engine in a city car/kei car application.

Dante Giacosa‘s Autobianchi Primula of 1964, Fiat 128 and Fiat 127, put the transmission on one side of the transversely mounted engine, and doubled back the drivetrain to put the differential just behind the transmission, but offset to one side. Hence the driveshafts to the wheels are longer on one side than the other. This located the weight just a bit in front of the wheels. It is this system which dominates worldwide at present.

Vehicles with the Giacosa arrangement tend to suffer from torque steer under heavy acceleration.[citation needed] The shorter drive shaft, being stiffer than the longer drive shaft, transmits the motion to the wheels immediately instead of ‘winding’ up due to the drive torque.[citation needed] The net result is more tractive force at the wheel with the shorter drive shaft and the car tends to pull to the opposite side.[citation needed]

BMC Mini 021

The bonnet on this older Mini is open, showing the transversely mounted engine that drives the front wheels.

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  • Misc:

Rear-engine, Front-Wheel Drive:

A rear-engine, front-wheel-drive layout is one in which the engine is behind the rear wheels, but drives the front wheels via a driveshaft, like a conventional front-engine, rear-wheel-drive vehicle traveling in reverse.

Although an uncommon drive layout, it has been used in the past, by Buckminster Fuller in his conceptDymaxion car, which was able to turn within its wheelbase due to rear-wheel steering.

There is some interest in developing the idea for use in cars of the future, as evidenced by the patent application of inventor–engineer Michael Basnett at Rover Group (GB), who proposes a front transaxle design, rear flat engine architecture.

Dymaxion car illustration

Dynamaxion 1933

Honda Civic typeR

Honda Civic Type R (FD2)

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Posted on July 21, 2012, in General, Uncategorized and tagged , , , , , , , , , , , , , , . Bookmark the permalink. 1 Comment.

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