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- 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 layout is typically chosen for its compact packaging, allowing the rest of the vehicle to be designed more flexibly. In contrast with the front-engine, rear-wheel drive layout (FR), the FF layout eliminates the need for a central tunnel or a higher chassis clearance to accommodate a driveshaft providing power to the rear wheels. Like the rear-engine, rear-wheel drive layout (RR) and rear mid-engine, rear-wheel drive layout (RMR) layouts, it places the engine over the drive wheels which may aid traction in many applications. As the steered wheels are also the driven wheels, FF cars are generally considered superior to FR cars in conditions where there is low traction such as snow, mud, gravel or wet tarmac. When hill climbing in low traction conditions RR is considered the best two wheel drive layout. However, very powerful cars rarely use the FF layout because weight is transferred to the rear wheels under acceleration, while unloading the front wheels and sharply reducing their grip, effectively putting a cap on the amount of power which could realistically be utilized. Electronic traction control can avoid wheel-spin but largely negates the benefit of extra power. This was the reason for the adoption of the four wheel drive quattro system by previously front wheel drive specialist Audi with the 1980 Audi Quattro for road cars. The pioneer of four wheel drive road cars was the Jensen FF in the 1960s for the same reasons. Early cars using the FF layout include the 1931 DKW F1, the 1948 Citroën 2CV, 1949 Saab 92 and the 1959 the original Mini. In the 1980s, the traction and packaging advantages of this layout caused many compact and mid-sized vehicles to adopt it. Because the transversely-mounted engine does not require a bevel gear to change the direction of the final drive, coastdown losses are reduced by approximately 2-3% of flywheel power and hence overall efficiency is slightly higher than with an FR design. There are four quite different particular arrangements for this basic layout, according to the location of the engine, which is the heaviest component of the drivetrain, with respect to the front wheels:
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![[RDF Data]](/statics/sw-cube.png)
