The cylinder head from a GMC van. The valves and part of the exhaust manifold are visible.

A 302/5.0L Ford cylinder head.

In an internal combustion engine, the cylinder head sits atop the cylinders and consists of a platform containing most part of the combustion chamber and the location of the valves and spark plugs. In a flathead engine, the mechanical parts of the valve train are all contained within the block, and the head is essentially a flat plate of metal bolted to the top of the cylinder bank; this simplicity leads to ease of manufacture and repair, and accounts for the flathead engine's early success in production automobiles and continued success in small engines, such as lawnmowers. This design, however, requires the incoming air to flow through a convoluted path, which limits the ability of the engine to perform at higher rpm, leading to the adoption of the overhead valve head design. Image File history File links Please see the file description page for further information. ... Image File history File links Please see the file description page for further information. ... GMC Logo GMC, formerly known as GMC Truck, is a United States-based brand name of trucks, vans, and SUVs. ... A van is a vehicle used for transporting goods or groups of people. ... A poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. ... Left side of a Ford Cologne V6 engine, clearly showing a (rusty) cast iron exhaust manifold - three exhaust ports into one pipe. ... Image File history File links Cylinderhead. ... Image File history File links Cylinderhead. ... The Ford Motor Company (usually called Ford; sometimes called FoMoCo), (NYSE: F) is a multinational corporation that manufactures automobiles. ... A colorized automobile engine The internal combustion engine is a heat engine in which the burning of a fuel occurs in a confined space called a combustion chamber. ... A piston and cylinder from a steam engine A cylinder in an internal combustion engine is the space within which a piston travels. ... A combustion chamber is part of an engine in which fuel is burned. ... A poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. ... This article or section should include material from Spark gap A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed aerosol gasoline by means of an electric spark. ... Ford flathead V8 engine, modified for power, depicted on cover of Hot Rod magazine Cover of Hot Rod magazine showing Ford Flathead V8 engine with centrifugal supercharger (on top) Flathead engine refers to an internal combustion engine that has the valves placed in the engine block beside the piston, instead... Piston engines are typically arranged with their pistons in rows, moving inside individual cylinders. ... An air flow bench is a device used for testing the internal aerodynamic qualities of an engine component and is related to the more familiar wind tunnel. ... Revolutions per minute (abbreviated rpm, RPM, r/min, or min-1) is a unit of frequency, commonly used to measure rotational speed, in particular in the case of rotation around a fixed axis. ...

In the overhead valve head, the top half of the cylinder head contains the camshaft in an overhead cam engine, or another mechanism (such as rocker arms and pushrods) to transfer rotational mechanics from the crankshaft to linear mechanics to operate the valves (pushrod engines perform this conversion at the camshaft lower in the engine and use a rod to push a rocker arm that acts on the valve). Internally the cylinder head has passages called ports for the fuel/air mixture to travel to the inlet valves from the intake manifold, for exhaust gases to travel from the exhaust valves to the exhaust manifold, and for antifreeze (coolant) to cool the head and engine. Double overhead cams control the opening and closing of a cylinders valves The camshaft is an apparatus used in piston engines to operate poppet valves. ... Single overhead cam (also SOHC) refers to the internal combustion engine design where one camshaft is located above the valves. ... rocker arm This page meets Wikipedias criteria for speedy deletion. ... A pushrod engine or overhead valve (OHV) engine is a type of piston engine that places the camshaft below the pistons (usually beside and slightly above the crankshaft in a straight engine or directly above the crankshaft in the V of a V engine) and uses pushrods or rods to... Crankshaft, pistons, and flywheel Continental engine marine crankshafts, 1942 For the comic strip about an old, curmudgeonly bus driver, see Crankshaft (comic strip). ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Left side of a Ford Cologne V6 engine, clearly showing a (rusty) cast iron exhaust manifold - three exhaust ports into one pipe. ... The word exhaust can mean:- A verb meaning tire out, as in After the long gallop, his horse was exhausted. ... Antifreeze is a water-based liquid coolant used in gasoline and diesel engines. ...

The number of cylinder heads in an engine is a function of the engine configuration. A straight engine has only one cylinder head. A V engine usually has two cylinder heads, one at each end of the V, although Volkswagen, for instance, produces a V6 called the VR6, where the angle between the cylinder banks is so narrow that it utilizes a single head. A boxer engine has two heads. Engine configuration is an engineering term for the layout of the major components of an internal combustion engine. ... Usually found in 4 and 6 cylinder configurations, the straight engine (often designed as inline engine) is an internal-combustion engine with all cylinders aligned in one row, with no or only minimal offset. ... A V engine is a common configuration for an internal combustion engine in which the pistons are aligned so that, if viewed along the line of the crankshaft, they appear to be in a V. Usually, two opposing pistons share one crank on the crankshaft. ... Volkswagen (pronounced folksvagen; meaning: peoples car; also known as VW or V-Dub) is an automobile manufacturer based in Wolfsburg, Germany in the State of Lower Saxony. ... The Ford Essex V6 engine A V6 is an internal combustion piston engine with six cylinders in a V configuration. ... // Description VR6 is an engine configuration developed by the Volkswagen Group. ... A flat engine is an internal combustion engine in which the cylinders are arranged in two banks on either side of a single crankshaft so that the motion of all the pistons is in a single plane. ...

The cylinder head is key to the performance of the internal combustion engine, as the shape of the combustion chamber, inlet passages and ports (and to a lesser extent the exhaust) determines a major portion of the volumetric efficiency and compression ratio of the engine. Volumetric efficiency in internal combustion engine design refers to the efficiency with which the engine can move the charge into and out of the cylinders. ... The compression ratio is a single number that can be used to predict the performance of any internal-combustion engine. ...

See also

• Crossflow cylinder head
• Engine tuning
• Head gasket