Inlet Manifold

In automotive engineering, an inlet manifold or intake manifold is the part of an engine that supplies the fuel/air mixture to the cylinders. The word manifold comes from the Old English word manigfeald (from the Anglo-Saxon manig and feald ) and refers to the folding together of multiple inputs and outputs.

In contrast, an exhaust manifold collects the exhaust gases from multiple cylinders into one pipe.

The primary function of the intake manifold is to evenly distribute the combustion mixture (or just air in a direct injection engine) to each intake port in the cylinder head(s). Even distribution is important to optimize the efficiency and performance of the engine. It may also serve as a mount for the carburetor, throttle body, fuel injectors and other components of the engine.

Due to the downward movement of the pistons and the restriction caused by the throttle valve, in a reciprocating spark ignition piston engine, a partial vacuum (lower than atmospheric pressure) exists in the intake manifold. This manifold vacuum can be substantial, and can be used as a source of automobile ancillary power to drive auxiliary systems: power assisted brakes, emission control devices, cruise control, ignition advance, windshield wipers, power windows, ventilation system valves, etc.

This vacuum can also be used to draw any piston blow-by gases from the engine's crankcase. This is known as a positive crankcase ventilation system. This way the gases are burned with the fuel/air mixture.

The intake manifold has historically been manufactured from aluminum or cast iron, but use of composite plastic materials is gaining popularity (e.g. most Chrysler 4-cylinders, Ford Zetec 2.0, Duratec 2.0 and 2.3, and GM's Ecotec series).

Read more about Inlet Manifold:  Turbulence, Volumetric Efficiency, Variable Length Intake Manifold

Other articles related to "inlet manifold, manifold, inlet":

D17A2 - ZC - DOHC ZC
... Inlet Manifold stamped PM7 ... No PGM-EFi plate on the inlet manifold, replaced with three ribs instead ... P29 stamped on inlet manifold ...
Inlet Manifold - Variable Length Intake Manifold
... Variable Length Intake Manifold (VLIM) is an internal combustion engine manifold technology ... The dynamic pressure is proportional to the square of the inlet air speed, so by making the passage narrower or longer the speed/dynamic pressure is increased ... Ford - The Ford Modular V8 engines sport either the Intake Manifold Runner Control (IMRC) for 4V engines, or the Charge Motion Control Valve (CMCV) for 3V engines ...

Famous quotes containing the words manifold and/or inlet:

    A large city cannot be experientially known; its life is too manifold for any individual to be able to participate in it.
    Aldous Huxley (1894–1963)

    Of lower states, of acts of routine and sense, we can tell somewhat; but the masterpieces of God, the total growths and universal movements of the soul, he hideth; they are incalculable. I can know that truth is divine and helpful; but how it shall help me I can have no guess, for so to be is the sole inlet of so to know.
    Ralph Waldo Emerson (1803–1882)