FIGURE 6.1 below shows a component of a four-cylinder in-line (straight) engine - NSC Mechanical Technology Automotive - Question 6 - 2023 - Paper 1

The main function of the crankshaft is to convert the reciprocating motion of the pistons into rotary motion. This transformation is essential for driving the vehicle and operating the engine.

The part of the crankshaft that is drilled to balance it is the crank web or counterweight. This modification helps to achieve a static balance by ensuring that mass is evenly distributed.

Static balance of the crankshaft occurs when the mass in all directions from the center of rotation is equal while it is at rest. This means that there should be no resultant force acting on the crankshaft, which helps to reduce vibrations and wear in the engine.

A vibration damper is typically mounted on the front end of the crankshaft of the engine. This location allows it to effectively dampen vibrations generated by the engine's operation.

The function of a vibration damper is to smooth or dampen the engine vibrations that occur during operation. This helps to maintain engine stability and prolong the lifespan of engine components.

Three different types of engine cylinder configurations are:

1. Inline / Straight
2. V-shaped (V Engine)
3. Flat / Horizontal

Two reasons for spacing the power strokes of an engine at equal intervals are:

1. To reduce engine vibrations, contributing to a smoother operation.
2. To ensure the smooth running of the engine, preventing performance fluctuations.

Three methods to determine the firing order of an engine include:

1. Reading from the vehicle specifications, often found in the owner's manual.
2. Checking the order written on the tappet cover, which indicates the firing sequence.
3. Examining the arrangement of valve rocks, particularly in the order of spark distribution from the distributor.

The term 'boost' refers to the increasing of manifold pressure above the normal atmospheric pressure in an engine. This results in a greater air-fuel mixture entering the combustion chamber, improving engine performance.

The two types of turbochargers are:

1. Variable Geometry Turbocharger (VGT)
2. Non-variable Turbocharger

Two reasons for fitting superchargers to engines are:

1. To increase cylinder pressure or compression pressure, improving horsepower.
2. To enhance the volumetric efficiency of the engine, allowing more air to enter for combustion.

Two mechanical drive systems commonly used to turn superchargers are:

1. Belt Drive
2. Gear Drive

A twin-charging forced induction system generally consists of both a turbocharger and a supercharger working together on the same engine to enhance performance and efficiency.

Two advantages of using a twin-charging forced induction system include:

1. Outstanding fuel economy due to efficient power management.
2. The ability to reduce/eliminate lag at low revolutions, ensuring immediate power delivery.