04.02.2015

SPARK PLUG

The main function of the spark plug is to conduct the electric current generated on the transformer to the combustion chamber, and turn it into high-voltage electrical spark, which will start the combustion, i.e., it is the item responsible for the correct burning of the air/fuel mixture.

At the time that occurs the electric spark between the electrodes of the spark plug, starts the fuel burning by creating a “fireball”. The “flame front” spreads along the combustion chamber burning the air/fuel mixture and promoting the expansion of gases.

Spark plugs with lower mass in the central and side electrode, as the Green, Platinum and Iridium spark plugs have more energy on “flame front”. This characteristic provides more efficient burning by reducing the level of emissions, providing fuel economy, improving engine performance and facilitating the starting.

Click below to learn more about the type of spark plugs:

·        Conventional Spark Plugs
·        Resistive Spark Plugs
·        Green Spark Plugs
·        V-Power Spark Plugs
·        Multiple Electrodes Spark Plugs
·        G-Power Spark Plugs
·        Laser Platinum Spark Plugs
·        Iridium Spark Plugs
·        Laser Iridium Spark Plugs
·        Racing Competition Spark Plugs
·        Semi-superficial discharge Spark Plugs
·        Future Trends for the Spark Plugs

 

The NGK Conventional Spark Plug began its development in 1930s in Japan and received several enhancements until the present day.

The release of the Super S type Spark Plug, which has nickel electrodes with built-in copper into the central electrode, guaranteed longer durability with an enlargement of the working heat range. With this, the use of copper built into the central electrode was extended to all NGK spark plugs.

With the appearance of onboard electronics in vehicles, NGK has developed in the late 1970s, resistive spark plugs that have a ceramic resistor, able to attenuate electromagnetic interference caused by ignition system. This interference is extremely detrimental to vehicle electronic systems such as:

– Electronic fuel injection;
– Sound system;
– Antitheft system (alarms, blockers and trackers);
– Automatic gear shift with electronic control;
– Traction and stability electronic control;
– Air Bag and ABS Systems.
– CAN Network;
– Air conditioning with electronic control;

 

During 1980s, automakers began to deal with increasingly rigid new laws of pollutant emissions. The Green Spark Plugs have been developed to meet this need, due to its unique configuration (central electrode with a shaped “V” cutting and concave side electrode). Its main advantage is that the spark occurs on the sides of the electrodes by increasing the energy of the flame front, providing a better fuel burning and also reducing the emission of polluting gases.

Other advantages of using Green Spark Plug are:

– Resistive type spark plug avoiding interference in electronic systems;
– Improved engine performance;
– Faster starting, even on cold days;
– Enables the use of more lean air/fuel mixtures;
– Excellent performance in gas powered vehicles (CNG – Compressed Natural Gas);
– Provides more stable idling speed;

In some markets, such as the North American, the Green Spark Plug, which has the spark occurring on the sides of the electrodes, is also known as V-Power Spark Plug

Multiple electrode spark plugs have high durability with a reduced cost and were widely used by the automotive industry in the 1990s. Another advantage is that it is resistive type, avoiding interference in electronic systems.

There are models of multiple electrode spark plugs with two, three or four lateral electrodes and regardless of the number of electrodes occurs only one spark at a time, always between the electrodes which have better ignition.

These are GP type Platinum spark plugs. It has platinum tip on the electrode central which, because it is a noble metal, has high resistance to wear.

The most significant gain of using platinum in the electrode of the spark plug is that, due to its great resistance to wear, enables the reduction of the diameter of the electrode, improving spark plug ignition and increasing its durability. This spark plug has the central electrode diameter of 0.6mm.

Other advantages of using platinum spark plug are:

– Greater fuel economy;

– Greater idle speed stability;

– Reduction in the emission of pollutants;

– Easier starting;

– Less possibility of misfiring;

– It is a resistive type spark plug avoiding interference in electronic systems.

 

These are P-type spark plugs containing platinum tip in the central electrode and platinum pad on the side electrode. With characteristics similar to GP type platinum spark plug, provides even better performance on static ignition systems, without distributor, because it combines the durability and ignition of the platinum in the two electrodes of the spark plug. This spark plug has the central electrode diameter of 0.8mm.

Some types of Laser Platinum spark plugs have built-in copper in side electrode too, valuing the heat dissipation of the spark plug.

These are IX type spark plugs containing Iridium tip in the central electrode, being the latest technology generation in spark plugs destined to high performance engines.

The Iridium is a noble metal which has high resistance to wear, allowing the reduction of the diameter of electrode and improving their ignition and durability. It has central electrode diameter from 0.4mm to 0.6mm.

Other advantages of using Iridium spark plug are:

– Greater fuel economy;

– Greater idle speed stability;

– Reduction in the emission of pollutants;

– Easier starting;

– Less possibility of misfiring;

– It is a resistive type spark plug avoiding interference in electronic systems.

 

 

 

These are IR type spark plugs containing Iridium tip in the central electrode and Platinum pad on the side electrode. They have characteristics similar to the Iridium IX spark plug, but with better performance on static ignition systems, without distributor, combining durability and ignition of the iridium with platinum

 

NGK produces special spark plugs for competition known as Racing Competition. The best known are the EGV type spark plugs, which have gold-palladium central electrode with a diameter of 1.00mm. It has a high power of heat dissipation, greater resistance to critical conditions of operation of competition engines and excellent ignition. These characteristics are highly required in engines prepared for high performance.

 

 

Applied in high performance competitions where the engines reach high operation rotations that generate high levels of mechanical vibrations. These spark plugs do not have side electrode and resist very well to the needs of high performance competition engines, offering a high degree of heat dissipation.

 

 

Modern engines are built on a concept of downsizing, based on reduction of the engine volume and increase its efficiency, that is, promote increase of propeller power, even with downsizing. Many of these engines are multivalve type, with more than two valves per cylinder (inlet and outlet valves).

These modifications result in a need for changes in spark plugs, because the head space available for installation of the spark plug is getting smaller. With this, the tendency of most modern engines spark plugs is becoming longer and thinner.

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