Transverse engine

A transverse engine is an engine in which the crankshaft is oriented side-to-side relative to the length of the vehicle. This is also sometimes called an east-west engine. Most modern front wheel drive vehicles use this engine orientation (with the exception of some Audis), while most rear wheel drive vehicles use a front-to-back longitudinal arrangement.

History
The first car known to use such an arrangement was a 1911 front-wheel drive car with a clutch at each end of the engine, driving the front wheels directly. The first successful transverse-engine cars were the two-cylinder DKW "Front" series of cars, which first appeared in 1931. After the Second World War, SAAB used the configuration in their first model, the Saab 92, in 1947. The arrangement was also used for Borgward's Goliath and Hansa brand cars and in a few other German cars. However, it was with Alec Issigonis's Morris Mini that the design gained acclaim, in 1959.

This design reached its ultimate extent starting with Dante Giacosa's elaboration of it for Fiat. He connected the engine to its gearbox by a shaft and set the differential off-center so that it could be connected to the gearbox more easily. The axleshafts from the differential to the wheels therefore differed in length, which would have made the car's steering asymmetrical were it not for their torsional stiffness being made the same. Now most small and small/medium sized cars built throughout the world use this arrangement.

The Lamborghini Miura used a transverse, mid-mounted 4.0 litre V12, a configuration that was unheard of in 1965, although now more common (e.g. Noble M12, Toyota MR2, Pontiac Fiero, Fiat X1/9)

The Land Rover LR2 Freelander, along with all Volvo models from 1998 on (including V8 models), employ a transversely-mounted engine in order to increase passenger space inside the vehicle. This has also allowed for improved safety in a frontal impact, due to more front to back engine compartment space being created. The result is a larger front crumple zone.

Transverse engines have also been widely used in buses. In the United States they were offered in the early 1930s by Twin Coach and used with limited success in Dwight Austin's Pickwick Nite-Coach. Transverse bus engines first appeared widely in the Yellow Coach 719, using Dwight Austin's V-drive; they continued in common use until the 1990s, though shorter V-configuration engines in a straight in "T-drive" configuration became common in the 1960s. They were also used in the British Leyland Atlantean and in many transit buses and nearly all double decker buses. They have also been widely used by Scania, MAN, Volvo and Renault's bus divisions.

Position placement of transverse engines
Engines may be placed in two main positions within the motor car:
 * Front-engine transversely-mounted / Front-wheel drive
 * Rear mid-engine transversely-mounted / Rear-wheel drive

Common types of transversely placed engines
Space allowed for engines within the front wheel wells is limited to the following:
 * Inline-two, Inline-three, Inline-four, Inline-five, V4 and V6 engines, some manufacturers have squeezed in inline sixes and V8s.