Ruthenium vs iridium spark plugs. These are the differences between them

In the automotive industry, spark plugs are vital to engine components. They help ignite the fuel for the engine to run and have a significant impact on its efficiency and performance.

While spark plugs have stayed unchanged in a vehicle’s engine over time, the only alteration has been from copper to platinum plugs and now the newer ruthenium and iridium spark plugs.

Both ruthenium and iridium spark plugs offer superior performance and increased durability to the internal combustion engine.

Since both are great options, most people find it hard to decide which plug to get. Here is an exclusive look at Ruthenium Vs. Iridium Spark Plugs to help you decide.

What are ruthenium spark plugs?

Ruthenium spark plugs are the new type of spark plugs made from a hard, rare metal that withstands high temperatures.

Ruthenium metal is being used in manufacturing spark plugs to resist corrosion and wear better than palladium or platinum. This means that your engine will operate more efficiently and be more durable with ruthenium spark plugs.

ruthenium vs iridium spark plugs
Ruthenium metal

Ruthenium is used as an electrode material for the engine’s ignition system due to its high resistance to corrosion and oxidation.

The ruthenium electrodes are more durable than those made from other metals like steel or copper. Ruthenium has a relatively high melting point of 4233° F or 2334 °C, although it’s lower compared to Iridium spark plugs.

What are iridium spark plugs?

Iridium spark plugs are one of the most durable and best plugs available in the market. Iridium is the most durable and densest metal on earth. This implies that your engine will operate cleaner and cooler after installing an iridium spark plug than it ever did.

iridium spark plug
iridium spark plug

With an excellent high melting point of 4471° F or 2466 °C, it can withstand high engine temperatures and is highly resistant to tear and wear.

This makes it a precious metal, making it expensive like platinum. However, iridium is currently about half the price of platinum.

These spark plugs have proven to last up to 120 000 miles or 193000, with some providing efficient functionality up to 150 00 miles or 2410000 km depending on the vehicle.

Differences Between Ruthenium Vs. Iridium Spark Plugs

When it comes to comparing ruthenium and iridium spark plugs, we can say that they both have differences, but also similarities.

Although they perform the same function and are among the best plugs, they are better than the others in some elements.

The important differences include:

1. Durability

When it comes to durability, ruthenium plugs are great! According to NGK, Ruthenium’s lifespan is higher than spark plugs made from other materials, including the platinum families.

Spark plugs made of Ruthenium are the latest technological development. Using ruthenium electrodes is said to extend spark plug life by two times as compared to modern iridium electrodes and by eight times as compared to standard nickel electrodes.

The electrodes of these plugs have increased wear resistance, meaning they can eventually become “lifetime” plugs that never need to be replaced. Further, they improve fuel economy, performance, emissions, and acceleration through better flammability.

Ruthenium is more resistant to corrosion and oxidation than iridium. According to NGK, Ruthenium plugs can last up to 200,000 miles or 321000 km.

On the other hand, Iridium spark plugs are designed to last for about 120 000 miles or 193000 km.

2. Design

In terms of design, iridium spark plugs come with a single design, while the ruthenium spark plugs are available in two different designs.

The designs, namely, projected square platinum electrode (PSPE) and double fine electrode (DFE), have different uses. The DFE plug minimizes discharges for low heat engines and maximizes ignitability, making it suitable for the non-turbo application. On the other hand, the PSPE is ideal for turbo and supercharged engines.

3. High ignitability

Ruthenium plugs have high ignitability. They guarantee maximum combustion, which ensures quicker fuel response, better acceleration, and complete fuel combustion.

Because of a faster cold start, the vehicle exhaust will release less raw gas in the opening minutes of running the engine. On the other hand, iridium has a faster response to the throttle operation and quickly improves your vehicle’s acceleration profile. You will feel the difference without losing time.

4. Fuel efficiency

Logically, newer spark plugs are more efficient than old spark plugs. When it comes to ruthenium vs. iridium spark plugs in fuel efficiency, it is said that ruthenium spark plugs win.

However, there is no certainty that this is indeed an advantage of ruthenium spark plugs over iridium ones. Using the ruthenium spark plugs, your vehicle’s acceleration requires less effort in the combustion process, which may enhance its fuel efficiency over time.

Iridium also helps in improving the fuel economy of your car when driving on a highway or city because of the enhanced ignition profile. Thus, the fuel efficiency rate is uncertain when comparing these types of spark plugs.

Are ruthenium spark plugs worth it?

Ruthenium spark plugs are one of the best to use in your car engine. One of the major advantages of ruthenium spark plugs is that they offer more mileage than iridium spark plugs. So, if you want to get more mileage-lasting plugs for your car, you should opt for ruthenium plugs.

Also, ruthenium spark plugs are more fuel-efficient. According to study tests conducted, switching from iridium to ruthenium plug helps to increase fuel efficiency by about ten to twenty percent.

Additionally, Ruthenium is an ideal option if you are on a tight budget. They are more affordable than iridium but still offer great value for your money. Therefore, you can purchase ruthenium plugs as they offer great performance and will save you money.

Are iridium spark plugs worth it?

Like Ruthenium, iridium spark plugs have their own disadvantages, such as being more expensive but providing benefits worth considering.

Iridium has more platinum levels than Ruthenium which gives the plug a higher melting point. Therefore, the iridium plug is more durable and high resistant to oxidation and corrosion. If you want your machine to run efficiently for years, the iridium spark plug is your best choice.

Another benefit of iridium plugs is lower voltage requirements compared to other spark plugs. This means you can efficiently run them on low-power engines.

This is excellent for those that don’t want to spend time or money upgrading the engine but still want to enjoy the qualities of an iridium spark plug.


Hopefully, you now understand the differences between ruthenium vs. iridium spark plugs. Whichever spark plug you go for will hence depend on your personal preference and needs.

The major difference is that Iridium spark plugs are more costly, but Ruthenium plugs seem to be more durable, although iridium has a higher melting point than ruthenium.

Otherwise, both plugs are a great option, reliable, and provide improved value and performance. So, you can choose any of them for your vehicle, and you will be more than fine.

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