CVCC is a trademark by the Honda Motor Company for a device used to reduce automotive emissions called a Compound Vortex Combustion Chamber. This technology allowed Honda's cars to meet the 1970s US Emission requirements without a catalytic converter, and first appeared on the 1975 ED1 engine. It is a form of stratified charge engine. The acronym gives the Honda Civic its name. A trademark (Commonwealth English: trade mark)[1] is a distinctive sign of some kind which is used by a business to identify itself and its products and services to consumers, and to set the business and its products or services apart from those of other businesses. ... Honda Motor Co. ... Pollution is the release of harmful environmental contaminants, or the substances so released. ... This article provides extensive lists of events and significant personalities of the 1970s. ... Emission standards limit the amount of pollution that can be released into the atmosphere. ... A catalytic converter in an automobiles exhaust system provides an environment for a chemical reaction where unburned hydrocarbons completely combust, using platinum and rhodium as catalysts. ... 1975 was a common year starting on Wednesday (the link is to a full 1975 calendar). ... The E-series was the first line of straight-4 automobile engines from Honda. ... The stratified charge engine is a type of internal-combustion engine, similar in some ways to the Diesel cycle, but running on normal gasoline. ... Acronyms and initialisms are abbreviations formed from the initial letter or letters of words, such as NATO and XHTML, and are pronounced in a way that is distinct from the full pronunciation of what the letters stand for. ... The Honda Civic is an automobile manufactured by Honda. ...

Construction and Operation

Honda CVCC engines have normal inlet and exhaust valves, plus a small auxilary inlet valve which provides a relatively rich air / fuel mixture to a volume near the spark plug. The remaining air / fuel charge, drawn into the cylinder through the main inlet valve is leaner than normal. The volume near the spark plug is contained by a small perforated metal plate. Upon ignition flame fronts emerge from the perforations and ignite the remainder of the air / fuel charge. The remaining engine cycle is as per a standard four stroke engine. A colorized automobile engine An internal combustion engine is an engine that is powered by the expansion of hot combustion products of fuel directly acting within an engine. ... 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. ... The four-stroke cycle of an internal combustion engine is the cycle most commonly used for automotive and industrial purposes today ( cars and trucks, generators, etc). ...

This combination of a rich mixture near the spark plug, and a lean mixture in the cylinder allowed stable running, yet complete combustion of fuel, thusly reducing CO (carbon monoxide) and hydrocarbon emissions. Carbon monoxide, chemical formula CO, is a colourless, odourless, flammable and highly toxic gas. ... In chemistry, a hydrocarbon is any chemical compounds that consists only of carbon (C) and hydrogen (H). ...

Advantages over previous stratified charge engines

Honda's big advancement with CVCC was that they were able to use carburetors and they did not rely on intake swirl. Previous versions of stratified charge engines needed costly fuel injection systems. Additionally, previous engines tried to increase the velocity and swirl of the intake charge in keeping the rich and lean mixtures separated. Honda was able to keep the charges adequately separated by combustion chamber shape. Cover of Popular Hot Rodding magazine, showing racing fuel injection system on V8 engine in the late 1960s Fuel injection is a technology used in internal combustion engines to mix the fuel with air prior to combustion. ...

References

Setright, L. J. K. (1975). Some Unusual Engines. London: Mechanical Engineering Publications Limited.