NAPS stands for Nissan Anti Pollution System a moniker used in Japan to identify vehicles built with emission control technology. The technology was installed so that their vehicles would be in compliance with Japanese Government emission regulations passed in 1968. The term was first introduced in Japan, with an externally mounted badge on the trunk of vehicles equipped. Nissan's implementation began with the Y44E V8 engine installed in the

Nissan President The is a Japanese luxury sedan that manufactured and marketed by Nissan from 1965 to 2010 as a JDM luxury sedan, the flagship of Nissan's range, marketed at its '' Nissan Motor Store'' dealerships. Initially marketed in the JDM, in the late ...

along with all vehicles installed with the

Nissan L engine , trading as Nissan Motor Corporation and often shortened to Nissan, is a Japanese multinational automobile manufacturer headquartered in Nishi-ku, Yokohama, Japan. The company sells its vehicles under the Nissan, Infiniti, and Datsun bra ...

and the

Nissan A engine The Nissan A series of internal combustion gasoline engines have been used in Datsun, Nissan and Premier brand vehicles. Displacements of this four-stroke engine family ranged from 1.0-liter to 1.5-liter and have been produced from 1967 till 2009. ...

in 1975. The initial introduction of Nissan's technology was the installation of an

exhaust gas recirculation In internal combustion engines, exhaust gas recirculation (EGR) is a nitrogen oxide () emissions reduction technique used in petrol/gasoline, diesel engines and some hydrogen engines. EGR works by recirculating a portion of an engine's exhaust ...

valve, followed with the addition of a

catalytic converter A catalytic converter is an exhaust emission control device that converts toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing a redox reaction. Catalytic converters are usual ...

and an air pump that added oxygen into the exhaust to promote higher temperatures in the catalytic converter, thus cleaning the exhaust further. The NAPS-Z technology, introduced in 1978, was developed with assistance from

Hitachi () is a Japanese multinational conglomerate corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Nissan ''zaibatsu'' and later DKB Group and Fuyo G ...

.Yamaguchi, Jack K., "Japan: Reluctant Number One", World Cars 1981: 66 It uses a novel implementation of two spark plugs per cylinder, called dual ignition together with electronically controlled fuel injection, installed on the

Nissan Z engine The Nissan Z engine is a series of automobile and light truck four-cylinder engines that was engineered by Nissan Machinery, manufactured by the Nissan Motor Company from 1979 through August 1989. All Z engines had 4 cylinders, a total of 8 valves ...

. This terminology is often confused with the engine installed in the

Nissan 280Z The Nissan S30 (sold in Japan as the Nissan Fairlady Z and in other markets as the Datsun 240Z, then later as the 260Z and 280Z) is the first generation of Z GT 3-door two-seat coupés, produced by Nissan Motors, Ltd. of Japan from 1969 until ...

, which used the "L" engine. However, the NAPS technology was installed in the Fairlady/Z and sold internationally. Another version of the twin spark plug method was introduced on the

Nissan Stanza In poetry, a stanza (; from Italian ''stanza'' , "room") is a group of lines within a poem, usually set off from others by a blank line or indentation. Stanzas can have regular rhyme and metrical schemes, but they are not required to have eit ...

with the CA engine, called NAPS-X, which eventually replaced the NAPS-Z approach. The CA engine implemented a hemispherical cylinder head, an approach used by several auto makers.

References

All links listed are in Japanese.
Datsun1200 Club - Tech Wiki - NAPS

Datsun1200 Club - Tech Wiki - EGR

* ttp://w01.tp1.jp/~a150584035/ackn/any/NAPS/NAPS.html 日産NAPS考察
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