Digital engine control systems
Traditionally, the term powertrain has been thought to include the engine, transmission, differential, and drive axle/wheel assemblies. With the advent of electronic controls, the powertrain also includes the electronic control…
Compression-ratio
In an engine cylinder, the gas molecules are moving about at considerable speed in the space occupied by the gas, colliding with other molecules and the boundary surfaces of the…
Engine cylinder capacity
Engine sizes are compared on the basis of total cylinder swept volume, which is known as engine cylinder capacity. Thus the engine cylinder capacity is equal to the piston displacement…
Engine power
Power is the rate of doing work. When applied to engines, power ratings may be calculated either on the basis of indicated power (i.p.), that is the power actually developed…
Engine torque
This is the turning-effort about the crankshaft’s axis of rotation and is equal to the product of the force acting along the connecting-rod and the perpendicular distance between this force…
Engine-performance terminology
To enable intelligent comparisons to be made between different engines’ ability to pull or operate at various speeds, we shall now consider engine design parameters and their relationship in influencing…
Crankcase disc-valve and reed-valve inlet charge control
An alternative to the piston-operated crankcase inlet port is to use a disc-valve attached to and driven by the crankshaft (Fig. (a)). This disc-valve is timed to open and close…
Reverse-flow (Schnuerle) scavenging
To improve scavenging efficiency, a loop-scavenging system which became known as the reverse-flow or (after its inventor, Dr E. Schnuerle) as the Schnuerle scavenging system was developed (Fig. Below). This…
Piston-engine cycles of operation
The internal-combustion engine The piston engine is known as an internal-combustion heat-engine. The concept of the piston engine is that a supply of air-and-fuel mixture is fed to the inside…
Future Developments in Automotive Transmission Systems
1. The CVT will gradually replace the conventional automatic transmission due to its high fuel efficiency and smooth gear shift. 2. The technology of semi-automatic transmission systems will also be improved to…
