Page 230 - Automotive Engineering Powertrain Chassis System and Vehicle Body

CH AP TER 8 .1 Types of suspension and drive

Fig. 8.1-49 Compact power train unit on the Vauxhall Corsa (1997). The engine is transverse mounted with the gearbox on the left.
The McPherson front axle and safety steering column can be seen clearly.

whereby the vehicle centre of gravity is pushed a long more space because of the torque converter. This space is
way forwards (Fig. 8.1-48). Good handling in side winds readily available with a longitudinally mounted engine.
and good traction, especially in the winter, confirm the A disadvantage of longitudinal engines is the unfav-
merits of a high front axle load, whereas the heavy ourable position of the steering gear: this should be
steering from standing (which can be rectified by power- situated over the gearbox. Depending on the axle design,
assisted steering), distinct understeering during this results in long tie rods with spring strut (McPherson)
cornering and poor braking force distribution would be front axles (Fig. 8.1-57).
evidence against it.
This type of design, as opposed to transverse mount-
ing, is preferred in the larger saloons as it allows for rel- 8.1.6.1.2 Transverse engine mounted
atively large in-line engines. The first vehicles of this type in front of the axle
were the Audi 80 and 100. Inclining the in-line engine In spite of the advantage of the short front overhang, only
and placing the radiator beside it means the front over- limited space is available between the front wheel hous-
hang length can be reduced. Automatic gearboxes need ings (Figs. 8.1-49 and 8.1-50). This restriction means that

Fig. 8.1-50 Layout of transverse engine, manual gearbox and differential on the VW Polo. Because the arrangement is offset, the
axle shaft leading to the left front wheel is shorter than that leading to the right one. The shifter shaft between the two can be seen
clearly. The total mechanical efficiency should be around n z 0.9.

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