Influential factors in the product development

In the development of new products, a multitude of influential factors, such as technical requirements and current legislation, must be taken into consideration.
The application of new technologies and legal provisions directly influences the development of new products

The worldwide discussion about environmental and climate protection, limited fossil resources and increasing petrol prices has altered public awareness considerably. Additional efficiency strategies for combustion engines, the use of new technologies and CO2-saving alternative fuels are demanded of modern engine concepts.

This presents great challenges for the automobile and supplier industries and has direct influence on the development of spark plugs, glow plugs and lambda sensors.

More efficient combustion and reduction of harmful emissions

Modern engines must fulfil increasingly strict environmental guidelines (keyword: Euro standards). Therefore, a great challenge lies in engine efficiency and the reduction of consumption as well as the reduction of harmful emissions. Through the development of wide-ranging technologies for spark plugs, glow plugs and lambda sensors, NGK supports the vehicle manufacturers in their respective strategies in the best possible way.


The engine bay of petrol engines is becoming increasingly smaller - with the same output. This is a trend referred to as "downsizing". Consumption and environmental pollution are reduced. In order to ensure that enough output is available, such engines frequently run with turbochargers and/or compressors. Intake and exhaust valves require a great deal of space in these engines, as do the coolant passages. This places special demands on dimensions, ignition reliability, thermal behaviour of spark plugs, etc.

Alternative fuels, e.g. gas operation

More and more engines are converted to "bivalent operation". That means: They can run on conventional petrol or a gas (LPG/CNG). For the spark plugs this means complicated conditions in regard to temperature load and ignition.


The replacement intervals defined by automobile manufacturers for spark plugs vary between 20,000 and 120,000 kilometres. This represents a challenge, as each ignition spark wears down a minimal amount of material. Through this "spark erosion" the electrode gap increases, thus leading to a higher ignition voltage requirement and, with that, higher stress for the ignition coil. These demands are met through the development of special spark plug technologies.

Related topics

Spark plug technologies: NGK produces spark plug technologies for every application - regardless of whether it is for normal road traffic, racing or for gas-powered engines.

Glow plug technologies: Glow plugs are basically differentiated between metal rod glow plugs and ceramic glow plugs. The two technologies have special characteristics in regard to thermal behaviour.

Lambda sensor technologies: There are lambda sensors for nearly every application. In this connection, specific technologies have very specific characteristics.

Exhaust and harmful emissions: Exhaust emissions are the non-useable gaseous waste products produced during the combustion process.

Fuels: Fuels are chemical compounds compounds whose energy content is release through combustion and is used for the creation of a propulsion.

Thermal behaviour: A spark plug must release a precisely defined measure of heat to the cylinder head. Only in this way can the optimal temperature window be adhered to.