1.2 Layout of components

The power units used in the light vehicle can be fitted in a number of different places (Fig. 1.1). The source of power is provided by an internal combustion engine. The petrol or spark ignition (SI) engine is the most common, although the diesel or compression ignition (CI) engine is becoming more widely used. These are of the conventional design, where the pistons move up and down in the cylinders. Several other designs have been used; for example the Wankel engine used by Mazda in the RX7 and by Norton in their motor cycle. Another method of propulsion is electricity; the electric vehicle is gaining popularity as there is very little pollution of the atmosphere and it can therefore meet the more stringent regulations coming into force each year.

Figure 1.1: Front engine RWD with integral body mountings

The layout of the main components may conform to one of the following:

• front engine front wheel drive (FWD)

• front engine rear wheel drive (RWD)

• mid-engine rear wheel drive

• rear engine rear wheel drive (Fig. 1.2)

  
  Figure 1.2: Rear engine RWD ideal layout for a two seater coupe

• one of the above but four wheel drive (4WD)