Iridium or platinum spark plugs, service life and main differences

Iridium and platinum spark plugs.

The service life of platinum candles is significantly higher than that of conventional ones. But it lags a little behind iridium ones. The service life of iridium spark plugs is considered maximum.

That is, the most reliable and durable are iridium spark plugs.

Difference between iridium and platinum spark plugs: The platinum spark plug has a slightly narrower center electrode. And on the side there is a platinum soldering.

But it is not as thin as an iridium spark plug.

An iridium spark plug has a central electrode 0.4 mm thick. About the size of a hair. The side electrode has a U-shape. Previously, the difference between them in cost was about 40%. An iridium spark plug was forty percent more expensive than a platinum spark plug. Although a platinum candle is also not cheap. But with the development of technology, their prices have almost become equal. The main thing is not to fall for a fake!

If you want to buy yourself platinum spark plugs, then the declared resource will be about 80,000 km. When purchasing a spark plug, be sure to pay attention to the side electrode. No one will ever put this small, barely noticeable solder on a fake. As for iridium spark plugs, counterfeiting them is much more difficult. The reason is the thin central electrode. If it is made of another metal and is not coated with iridium, then there is a risk of it quickly burning out. And for every purchase, as you know, you are required to provide a guarantee. It is for this reason that they are rarely counterfeited. But in the Celestial Empire they can fake anything. So, be careful when choosing a candle!

Pay attention to the side electrode. It should be made in a U-shape.

And the declared service life of iridium spark plugs is more than 100,000 km. If it is difficult to change spark plugs on your car, you have a “fresh” engine and low mileage, then pay attention to iridium or platinum spark plugs. Once you install them, you won’t have to look there again!

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Marking of Denso spark plugs

Video: Spark plugs in Japanese cars: marking of Denso, NGK spark plugs

Each manufacturer uses its own coding scheme for spark plug parameters. Denso has adopted the following for new series:

Iridium TT candles have their own scheme:

Old marking system:

For example, let's find an analogue of our classic candle A17DVRM. Here the difficulty is only with the heat number (Denso does not provide comparisons with the domestic standard), but from the catalog of analogues we can conclude that Denso’s analogue of the Russian “17” will be “20”. Since we need a 14x19 threaded shank, and the spark plug wrench we use is 21, we need to look for spark plugs with the W20 prefix in the “old” series (since VAZ spark plugs have been replaced for decades) - for example, W20EPR-U, spark plugs with 19mm shank (E), center electrode protrusion (P), built-in resistor (R) and U-shaped groove on the side (U). If you want to install iridium spark plugs, then IW20TT will do.

Iridium

Iridium is the hardest silvery-white metal on the planet. Its electrical resistance is second only to gold and silver, and its melting point (2454°) is second only to molybdenum (2620°) and tungsten (3420°). In addition, the precious metal iridium does not oxidize during combustion.

The properties of iridium lead developers to use the metal in the central electrode. Its resistance to deformation, strength and ability to withstand heavy loads are manifested in alloys; without them, working with metal is impossible due to the fragility of the material and low electrical conductivity.

Peculiarities

Iridium spark plugs are distinguished from other products by their thin tip width, achieved through laser welding of the electrodes and iridium as a conductor. The average thickness using iridium is 0.4 mm, while the thickness of alternative types and subtypes is from 1.5 mm to 2.5 mm.

A thin rod allows you to concentrate the charge of electricity on a small area, rather than dissipate it over the entire surface in the case of a larger electrode area and, as a result, increase the quality of the spark gap.

Thanks to this system, fuel burns as completely as possible, regardless of the selected speed mode, and the engine runs smoothly without interruptions.

Denso IW20, Denso WEPR

It’s not easy to pay about 3,000 rubles for a set of candles, knowing that your neighbor paid less than a hundred for similar ones. All the advantages of an expensive purchase are only in the future: the long mileage promised by advertising, some percentage of daily fuel savings, ease of starting... In addition, there is no need for frequent replacement: on a modern engine this is a labor-intensive and expensive procedure.

We decided to evaluate two polar designs from one reputable company in order to compare not the technology of different manufacturers, but the idea itself embodied in metal, all other things being equal. The choice fell on Denso.

Iridium IW20 are the obvious leaders in miniaturization of the central electrode: only 0.4 mm. It is the thin electrode that promotes better self-cleaning and, accordingly, extends the service life. They were accompanied by the usual W20 EPR-U. The initial difference in cost is approximately fivefold.

An increase in CH toxicity indicates disturbances in the combustion process.

An increase in CH toxicity indicates disturbances in the combustion process.
An increase in CH toxicity indicates disturbances in the combustion process.

According to the resource, the count in engine hours is 360:240. In all operational parameters - from consumption to toxicity levels - iridium is also confidently ahead.

Hence the conclusion: if you have an expensive modern car and you put a lot of miles on it, it makes sense to spend money on iridium. But if the car is so-so, and only travels no more than 5 thousand a year, you are unlikely to recoup the investment. Such is the deceit of expensive things...

Mikhail Kolodochkin, and associate professor of the department of internal combustion engines of the St. Petersburg Polytechnic University, Ph.D. Alexander Shabanov

Choosing spark plugs: iridium or regular?

Advantages

Experiments to improve standard products were not in vain. The properties of iridium and the characteristics of iridium spark plugs have led to a number of advantages over outdated products made from other metals and alloys. Among which:

The use of a product using iridium on average increases the overall engine power by 7%. In some situations the percentage increases more and leads to tangible improvements;
The service life of iridium spark plugs significantly exceeds other types and subtypes. Replacement is required no more often than after 100,000-150,000 km (the service life of previous types and subtypes is 10,000-20,000 km). It is this property that compensates for the high cost of a product using iridium;
the required fuel costs are reduced by 7%, due to a more powerful spark providing volumetric ignition. In addition, toxic emissions that are harmful to the human body and the environment are also reduced;
It doesn't take much effort to start the engine. Even in adverse weather conditions (low temperatures), the engine starts quickly and without additional assistance. This property is especially important in areas with harsh climates, where the temperature in winter drops to 40°.

Thus, manufacturers not only corrected the problems of previous products, but also introduced a number of new advantages.

Flaws

Despite improvements, iridium spark plugs need to be refined and improved. The advantages and benefits of candles using iridium are complemented by several significant disadvantages, including:

There is a significant difference in price between iridium spark plugs and regular spark plugs. At the same time, the purchase of simple spark plugs cannot be called profitable or economical, since the service life of iridium spark plugs is many times longer. Choosing a product based on pricing is wrong and can lead to even greater waste;
unjustified use on conventional engines. Iridium spark plugs are aimed at modern models and for high mileage; if both the first and second are missing, all the positive aspects, with the exception of increased service life, disappear. Combining iridium spark plugs and an old car model will not bring impressive results.

If the first minus is justified by the quality and service life, then the second directly affects the decision to purchase iridium spark plugs. The costs will not be recouped without a powerful engine and frequent use of the car.

When is it still necessary to change spark plugs?

Like any replaceable elements in a car, spark plugs can be replaced as planned during operating hours or emergencyly as a result of a failure. In the first case, when carrying out the next maintenance of the car in a service center or independently, it is recommended to replace the spark plugs when the car's mileage reaches within 10-15 thousand kilometers, regardless of their condition. At the same time, we advise you not to throw away the removed candles, but to hide them, just in case, in a place that is easily accessible to you.

It should be noted that with this approach, you deliberately incur additional costs associated with the early purchase of a new set of spark plugs, but you save yourself from headaches by preventing forced emergency situations. In case of unstable engine operation due to poor sparking of the ignition system, it is necessary to remove the spark plugs from the car, inspect their condition and, if defects are detected, replace them with new ones. We do not recommend attempting to “reanimate” these components yourself at home (calcination, ultrasonic cleaning, restoration of insulation, etc.), since even if you achieve a certain result, it will most likely be temporary and short-term. If one or more spark plugs fail, we recommend replacing the entire set or replacing the faulty ones with products of exactly the same type and manufacturer.

PRICE

An insignificant and compensated minus in fact becomes the main argument “against” for motorists when purchasing. The cost of iridium candles is more than double the price tag of conventional ones. The main reason for this is the high demand in the market. Rare and precious metal also causes high prices, however, to a minor extent. The total mass of iridium in the electrode is low, since only the tip is made of precious metal, which leads to a low impact on the final cost of the spark plug.

The cost of iridium spark plugs is variable and will decrease if demand decreases. At the moment, more than 20% of the total amount of iridium is spent on making candles. If the figure increases, the price tag will increase by an undetermined amount; if it falls, it will decrease. There are two possible reasons why the percentage will change soon:

reducing the percentage of old cars on the market and popularizing cars with more powerful engines, making them accessible to all segments of the population. This will lead to an increase in the price of iridium spark plugs;
the invention of new, more efficient products using a different type of metal or alloy, which will lead to a reduction in the price of candles using iridium.

Until the first or second circumstance occurs, iridium spark plugs are gaining popularity, slowly capturing the market and displacing obsolete products.

What about the high price?

The main problem when choosing iridium spark plugs is their cost, which forces car enthusiasts to give preference to more affordable products.

But here it is important to note that candles using iridium will be cheaper than platinum products, which are also considered one of the best.

There is an opinion that the inflated cost is due to the rarity of the metal, because iridium is less common than gold or platinum.

In fact, price formation occurs according to a different principle.

Manufacturers focus on the demand for specific products, the characteristics of the automotive spare parts market, the presence of competition, and so on.

Today, purchasing iridium spark plugs will cost less than platinum spark plugs. But this situation can change at any moment.

In practice, almost a fifth of the rare metal that is mined on the planet is spent on the production of iridium candles.

As for the more famous platinum, it is mostly used for making jewelry, with only a small percentage involved in the production of candles.

An important point is the amount of metal used in production.

As in the case of iridium and platinum spark plugs, the use of expensive materials is minimal.

Only two elements are made of iridium or platinum - the grounding electrode and the tip of the part.

As soon as the demand for candles using iridium increases, the consumption of this metal increases and the price increases.

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When to replace

Recognizing wear or malfunction of spark plugs is quite simple; you need to carefully observe your car and notice signs such as:

Fuel consumption has increased several times over the last week and month, but the car itself shows no signs of breakdowns;
The car does not start after the first attempt, you have to try hard to get it to go;
And if problems arise when gaining speed.

The catch may be the fact that such “symptoms” may indicate malfunctions of the spark plugs and other systems of the car - the gas pump, fuel supply, air filter or even the exhaust system.

Why iridium?

Such a wide selection of candles pampers car enthusiasts only for 20-25 years. Before this, the choice was much poorer.

Platinum candles were already on sale, but one could only dream of decent quality or reliability.

The best manufacturers in the world did everything possible to improve the quality of the product and achieve their goals, namely ensuring maximum reliability, long service life and reducing energy consumption.

In 1994, NGK specialists finally managed to create high-quality spark plugs using a special material - iridium.

What are its advantages? — It has a maximum melting point (in this indicator, iridium surpasses even platinum), excellent anti-corrosion properties and high quality.

The developers managed to make the thickness of the electrode minimal. Moreover, it was the tip that was made of rare metal.

In terms of its hardness, iridium occupies one of the leading positions. Many believe that the metal is based on the material of a meteorite that arrived on our planet many millions of years ago. Hence its hardness indicators.

Another advantage of iridium is its ability to withstand high temperatures. Metal can only be melted when heated to 2,500 degrees Celsius.

Iridium has been actively used in the industrial sector (since the 20s of the last century). But in practice it is not used in its pure form, but in the form of a special alloy.

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This is not surprising, because without the addition of metals, iridium is extremely fragile and useless in production. That is why in practice only alloys are used.

What is iridium and its history

Currently, many car enthusiasts prefer iridium spark plug sets. This is due to the long service life of the products, the highest quality and long service life, which increases the power of the vehicle. Their only drawback is the high price, which not everyone can afford. The high cost is explained by the fact that iridium is a rather rare and hard metallic formation.

It is believed that the material appeared many years ago on our planet due to meteor showers. In addition to the above properties, there is one more merit that makes it indispensable in the automotive industry - its high melting point (2500°C) . However, as it turned out, in its pure form the material does not possess all of the above properties. Since it itself is more fragile and has lower electrical conductivity. Therefore, they began to use it only at the end of the 20th century, and then as part of various alloys, which just complemented the missing properties.

Replacing spark plugs

Selection options

We won't talk much about the choice. The choice is made in accordance with the technical parameters of a particular vehicle. When purchasing, it is important to buy the original and not a fake; we will tell you more about their differences below. Denso's official website offers a great opportunity to consumers. In accordance with the parameters entered into the form about the car, the system automatically calculates and provides the user with SZ models, the use of which is allowed in the car.

NGK or Denso?

There are currently many manufacturers of spark plugs: you can buy iridium spark plugs either from a large factory with a well-known name or from a small Chinese company.

Candles from two companies are in stable demand - Denso and NGK. Whose products should you choose?

Denso iridium spark plugs are the latest generation of products; their service life can reach 7 years. The developers managed to reduce the electrode to 0.4 mm, which guarantees a soft start of the engine in any weather. In addition, Denso spark plugs reduce the time it takes to accelerate a car, reduce engine noise when idling and reduce fuel consumption.

NGK spark plugs are of equally good quality: it is not without reason that many automakers use them for standard equipment in the cars they produce.

The choice of manufacturer is a matter of personal preference, since both companies supply high-quality products to the market without having obvious advantages over each other. The main thing is not to forget that the more famous the company, the higher the risk of running into a fake , so it is better to buy candles in specialized stores that have quality certificates for the goods they sell.

Where to buy quality goods?

Experts and drivers with extensive experience advise that when answering the question of how often it is necessary to inspect and change spark plugs, adhere to the manufacturer’s recommendations. This is approximately 30,000 km of mileage by car.

“hot” product , which is used by unscrupulous businessmen. Counterfeit brands are offered everywhere. There is no need to talk about the quality of such a product. Car markets and some small shops on highways and city outskirts are considered a hot spot. Passing motorists buy the product, replace it, and after a short mileage are forced to repeat the replacement operation. This is usually already far from the place of purchase. Therefore, you should purchase goods from time-tested suppliers with an unblemished business reputation. Where can they give a quality guarantee?

In custody

I would like to remind you that, paradoxical as it may sound, you yourself should know the answer to the question of how often and when you need to change the spark plugs on your car. After all, you are its owner and, in most cases, the driver. Listen to the operation of the power unit and look at the speedometer. There is no need for a nanny in this matter!

Main characteristics of iridium spark plugs

The secret of modern iridium spark plugs is that the electrodes are connected using laser welding. Due to the good conductivity of the material, it allows you to create very thin tips of a very small size, which is very advantageous in comparison with the use of copper and platinum. In addition, this does not in any way affect the service life of iridium spark plugs.
Set of iridium spark plugs
The small diameter of these spark plugs creates a more concentrated electrical charge, which in turn allows for a small voltage to be created to cross the spark gap. This will make the car run smoother, accelerate faster, and improve combustion during any type of driving. Iridium allows the electrodes to be at an equal distance at all times and hold the spark.
Number of side electrodes. The standard option is one central and side electrode. Models appeared consisting of two, three, and four electrodes. New – without side electrodes.
In addition, iridium has the highest strength and the ability to consistently maintain a spark. Iridium will retain all its advantages in any situation. Its density is 22.65 g/cubic. cm. Because of this, the material is heavier than osmium. The hardness of the element is 6.5 on the Mohs scale, does this mean that the material is not subject to wear.
Due to the high melting point of iridium alloy, it is suitable for use in most high-tech engines with high operating efficiency. The temperature of the working spark plug in all engine operating modes should be somewhere between 500–900 degrees Celsius.
Trivalent nickel coating perfectly protects parts from corrosion. Much less voltage is required to create a spark, since the entire potential difference is concentrated in the tiny tip of the spark plug. In addition, iridium can improve vehicle acceleration and increase fuel efficiency.
Iridium spark plugs DENSO

Basic properties

The first company to use iridium, thereby improving the quality of SZ, was the Japanese company NGK. The reason why iridium was chosen was that this metal has a very high melting point, exceeding even platinum. In addition, it has high resistance to corrosion processes.

The reliability of spark formation can be increased by increasing the gap between the electrodes or reducing the diameter of the central electrode due to the use of chemically resistant noble and refractory metals for its manufacture. If you increase the gap, it becomes necessary to increase the voltage for sparking. When using noble metals, the cost of protective equipment increases. Manufacturers have taken both paths.

Since the 1980s, iridium in the form of an alloy has been used to produce igniters. Due to its fragility and low electrical conductivity, iridium is not used in its pure form. Its best properties are manifested in alloys. Iridium electrodes are made by laser welding. The iridium alloy is a good conductor, so it became possible to reduce the diameter of the central electrode.

Due to the small diameter of the tip, high voltage is not required to form a spark; the charge is concentrated on a minimal area. Therefore, high-quality ignition is guaranteed in any driving mode, and the fuel will burn completely. The engine power increases, it runs smoothly without failures, which allows you to quickly gain speed. Iridium maintains a constant gap between the electrodes, ensuring the safety of the spark and eliminating problems with starting the power unit.

The following main properties can be distinguished:

the high melting point of iridium alloys makes it possible to use these products for high-tech engines;
iridium tips of minimal diameter have high strength, which guarantees a constant spark to ignite the fuel assembly and start the engine in any weather;
Nickel coating of devices increases anti-corrosion and anti-blocking properties;
the voltage is supplied to the thin tip, so large values are not needed for sparking;
Iridium SZ have good efficiency during fuel combustion;
Long service life due to the high melting point of iridium.

Maintenance and replacement of spark plugs

Although manufacturers of iridium spark plugs for cars claim that they need to be replaced every 150-160 thousand kilometers , experts recommend doing this somewhat more often. This is due to the fact that the duration and efficiency of their operation are strongly influenced by the frequency of engine starting and the quality of its operation, the quality of fuel, the level of environmental pollution, etc. You will not see standard iridium spark plugs in Russian-made cars, since there is no such thing in the country the necessary specialized equipment.

It makes sense to buy iridium kits only for owners of expensive cars with mileage exceeding 5 thousand km per year.

When you select a replacement for worn parts, you need to pay attention to the thread diameter, length and pitch, but the configuration of the wires may differ from what was in the original. You should also pay attention to the heat rating; if it is selected incorrectly, then either carbon deposits on the spark plug or detonation of the engine cylinders will occur. Soot on spark plugs occurs when energy leaks into the housing while the power between the side and center electrodes is weakened. Therefore, before purchasing, you need to rely only on the recommendations of the manufacturer of your vehicle.

How to distinguish an original Denso from a fake?

In order not to waste money in vain, we recommend that you familiarize yourself with how to properly buy the original. Diagnostics of the purchased product can be carried out both by the appearance of the device and by its internal structure.

Naturally, when buying spark plugs, you will carry out visual diagnostics:

Inspect the product carefully. In original spark plugs, the surface of the contact terminal is more matte. As for fakes, they have a glossy surface.
Pay attention to the inscriptions indicated on the case. In counterfeit products, if necessary, the text can be removed with a fingernail or a coin, and this can be done very quickly. In original products, it is almost impossible to remove text, or at least it is much more difficult to do so.
Carefully inspect the threads of the device and the electrode. The actual quality of these structural elements in fakes is lower, this will be noticeable.
If we talk specifically about the housing of the devices, then in fake products it is not as high quality as in the originals. In particular, in this case it means that the surface of the case is not processed so well.
If you do buy a fake, then when operating the car you will notice that when driving uphill or at high speed, the engine power may decrease for no reason. But then she can also recover on her own. Accordingly, fuel consumption when using counterfeits may also be higher. The difference is not critical, but you can trace it only with accurate flow measurements.
With prolonged use, the side electrodes of the products may begin to melt. This can be monitored by periodically checking the status.

How to choose candles

Denso iridium spark plugs should be selected based on the recommendations of your car manufacturer. How not to make a mistake when choosing, and most importantly, is there any point in such an expensive purchase? The main feature of spark plugs using iridium is the small thickness of the central electrode. This helps to better clean the spark plug from soot, which is always present in a running engine. The obvious benefit of high-tech spark plugs is that they need to be changed much less often, because this procedure is often quite difficult. But there is one “but”... It all depends on the quality of Russian fuel. It does not kill iridium spark plugs as quickly as regular spark plugs, but they often do not reach their full service life. Therefore, it only makes sense to buy iridium or platinum for owners of expensive cars whose annual mileage exceeds 5,000 km. There is no particular need to install iridium spark plugs on a VAZ, since they are quite easy to change on our cars, and the quality of Russian gasoline is different from European. Which iridium spark plugs are better? One of the main characteristics of a spark plug, regardless of its type, is its heat rating. The spark plug accumulates heat during engine operation. If the heat value is chosen incorrectly, then two scenarios are possible: detonation of the engine cylinders or fouling of the spark plug and its failure. Spark plugs have become almost a mythical attribute of the car, judging by what they write on car forums. The reality is that in Russia, ngk iridium spark plugs and other expensive spark plugs cannot withstand more than 50,000 km, although they are designed for a longer service life. The application of noble metals to the electrode increases the life of the spark plug and reduces the gap between the electrode and the insulator.

How long do spark plugs last on a car and how often do you change them?

Let's try to figure out how often you have to change spark plugs in a car, what causes their failure.
The question is not idle - after what period of time and how often do the spark plugs on a car ? Naturally, opinions differ. There is no clear answer. For one type, replacement is required after a run of 10,000 km; for others, 80,000 km is not the limit.

Short. Just in case!

Spark plugs in an internal combustion engine are the key to starting the combustion process of the air-fuel mixture in the cylinders of a car’s power unit. Misfire of even one of them significantly reduces the power of the power plant. The emission of harmful gases into the atmosphere is increasing. The malfunction problem may be due to a manufacturing defect or late replacement.

NEGATIVE QUALITIES

The first thing that catches your eye is the high price of such candles. But given the long service life, high vehicle efficiency, excellent quality and temperature resistance, the price is justified, although it is higher than standard copper spark plugs.

Depending on the car model, iridium spark plugs may provide little or no performance improvement - it depends on the current state of the car. In addition, special engine efficiency is not always required and many vehicles will be limited to standard kits. Their use in conjunction with small-displacement engines is not recommended - such an expense will not be justified.

SERVICE

The operation of iridium kits has not changed over the past few years. They will still last over 100,000 miles on most cars, but manufacturers advise replacing them much more frequently, as frequent ignition, external contamination, and engine problems can reduce service life.

When choosing iridium spark plugs, the coincidence of the configuration with the old ones is not important, but the pitch, length and diameter of the thread must match, otherwise the installation will fail.

SPARK PLUG GAP – IS IT NEEDED TO BE ADJUSTED?

For some drivers, the issue of setting the gap is questionable. They can be understood, because the kits are produced with the gap set at the factory, and the engines of the cars are different. Still, there is no need to worry, because when we buy a kit for our model, we receive ready-made samples that only need to be re-adjusted when repairing the engine or cleaning the spark plugs themselves. For example, Denso products have a factory-set gap. Before installing new ones, it is recommended to check the spark plug visually for bent electrodes.

IS IT WORTH INSTALLING IRIDIUM PLUGS ON OLD CARS?

Is it worth installing iridium samples on old cars that have driven hundreds of thousands, or is it better to get by with a more budget option? This is a difficult question that cannot be answered unequivocally. The question here is, first of all, economic feasibility. On new injection models, expensive iridium options pay for themselves quite quickly. This happens not only due to improved technical characteristics of the engine, but also due to reduced maintenance costs, as well as a significant reduction in fuel consumption - and such spark plugs pay for themselves quite quickly.

An old carburetor car, regardless of whether it has iridium or regular spark plugs, will not “drive better”, and there will be no significant savings on gasoline. However, the operation of the ignition system will undoubtedly improve and become more stable, starting the engine in cold weather will be easier, and the engine will stop reacting violently to low-quality gasoline. Car maintenance is also important, especially one that runs on liquefied gas. Thus, installing modern spark plugs can significantly increase the comfort when operating a car, but it is unlikely that you will be able to save on the rest.

New product on the automotive spare parts market

Iridium spark plugs are a relatively new product, which, despite the fact that they have been on the market recently, have already gained popularity among many car enthusiasts. The design of the candles was already installed in the very first samples, and therefore the new product is practically no different from its analogues. Manufacturers' efforts are aimed at improving technical characteristics, since the principle of operation always remains the same. There's no point in reinventing the wheel. Therefore, manufacturers are working to increase the service life of iridium spark plugs, and reviews from many drivers are proof of this. No less attention is paid to how reliably the spark works. This will allow the fuel mixture to burn completely. In this regard, each subsequent generation of spark plugs allows you to save on fuel. Also, many manufacturers are addressing the issue of reducing harmful emissions into the atmosphere.