intake stroke

The valves can open several times per intake stroke, based on engine load.

This results in a greater mass of air entering the cylinders on each intake stroke.

The intake valves also close earlier during the intake stroke.

By the time the piston reaches the bottom of its intake stroke, the air/fuel is moving at a pretty high speed.

The fuel is injected during the intake stroke.

Intake stroke: Air and vaporized fuel are drawn in.

A mix of petrol and air is drawn into the engine cylinder on the intake stroke.

In a car engine, therefore, all of the fuel is loaded into the cylinder during the intake stroke and then compressed.

In Compression Ignition engine, first of all the air is compressed after the intake stroke.

Under light load, the throttle is not fully open, and the cylinders receive less than a full charge of air on each intake stroke.

A port injection system injects fuel just prior to the intake stroke (outside the cylinder).

This involves closing the intake valve midway through the intake stroke.

This is the intake stroke.

Intake stroke - The intake valve opens up, letting in air and moving the piston down.

Fuel is injected during the intake stroke, creating a homogeneous fuel-air mixture in the cylinder.

Furthermore, fuel is injected during the intake stroke and not at the end of the compression stroke as in a diesel.

In the engine proposed by Ward, the intake stroke is physically shorter than the expansion stroke.

Inertial supercharging effect is the result of incoming fuel/air charge developing momentum greater than intake stroke would generate alone.

The fuel is not injected at the intake stroke but rather at the latter stages of the compression stroke.

In urban running, the inlet valves open twice during an intake stroke to get better swirl and combustion of the petrol/air mix.

In the hot-bulb engine, before 1910 fuel was injected earlier into the vapouriser (during the intake stroke).

During the intake stroke, fresh air is inducted into the cylinder through a mechanically operated intake valve.

This two-stage intake stroke creates the so called "fifth" stroke that the Miller cycle introduces.

Let air come in more easily - As a piston moves down in the intake stroke, air resistance can rob power from the engine.

To put that in perspective, there is something like 2 teaspoons (10 cc) of nitromethane being poured into each cylinder per intake stroke.