thumb|Longitudinal engine in a [[three-wheeler chassis]]
thumb|240px|Longitudinal [[inline-six cylinder engine in a Henderson De Luxe Supersix of 1926]]
In automotive engineering, a longitudinal engine is an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, from front to back.
Cars with longitudinal engines usually have a smaller minimum turning circle than those with transverse engines. This is because there is more space to the sides of the engine, allowing deeper wheel arches so the front wheels are able to turn through a greater angle.
In the late 1960s, GM divisions Oldsmobile and Cadillac had front-wheel drive models Toronado and Eldorado respectively, with a longitudinal V8 engine and an integrated automatic transmission and differential unit powering the front wheels. Honda and Toyota also offered front-wheel drive cars with longitudinal engines, namely Honda Vigor, Acura/Honda Legend/RL, and Toyota Tercel.
Common types
The following is a list of typical examples of types of engines which can be placed in motor vehicles:
- In-line or straight engine – where two, three, four, five, six, and even eight cylinders are placed in a single plane.
- V engine – where two, four, six, eight, ten, twelve, or even sixteen cylinders are placed in two separate planes, looking like a "V" when viewed from the end of the crankshaft.
- Flat or boxer engine – where two, four, six or more cylinders are arranged in two diametrically horizontally opposed planes.
- W engine – where two (narrow angle) vee engines are siamesed together (within 180°), where at eight, twelve or sixteen cylinders are arranged in four separate planes.
References
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