The 11 Best Spark Plugs of 2024

Although it is one of the smallest components of your car’s engine, a spark plug is an equally important part. It plays a significant role in the engine to make your car move from one location to another.

The best spark plugs are responsible for triggering an explosion in the cylinders within the engine when a mixture of air and gasoline is ignited. Deep inside the engine, air and fuel are taken in to be compressed by powerful pistons. This happens just before the mixture is ignited several times per second. The ignition leads to the creation of an energy-dense explosion that produces enormous power to drive your vehicle.

When an electric current flows between the ground electrode and center electrode of a spark plug, a tiny spark is created. It is this small spark that causes the explosion of a mixture of fuel and air, producing immense energy that moves the pistons. The movement of pistons causes a rotary motion that drives the car.

Although they are small, inexpensive, and often overlooked, the best spark plugs act as the starting point of your engine’s working mechanism. That is why they need occasional maintenance. Mostly by removing worn-out or outdated plugs and replacing them with new ones.

Spark plugs, just like any other component in the engine, wear out and wear down after a certain period of time. Due to this wearing process, they reduce your car’s fuel economy, lower its performance or cause damage to the engine.

So replacing old and worn-out spark plugs is one way of keeping your vehicle in good working condition. Below is a review of top-pick spark plugs that you can find on the market today.

Best Overall: NGK-6619 LFR6AIX-11 Iridium Spark Plug

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NGK-6619 LFR6AIX-11 Iridium Spark Plug is designed specifically to meet the needs of all motorist enthusiasts. This model offers improved throttle response, extreme ignitability, and superior anti-fouling to give you the best results when driving.

It’s 0.6mm laser welded fine tip is built to provide high durability including a consistently stable spark. The tapered ground electrode on this spark plug minimizes what is known as the electrical quenching effect to enhance performance.

On the other hand, the longer insulator nose helps to prevent fouling. Also, the corrugated ribs on the insulator minimize cases of flashover while the triple gasket seal prevents combustion gas leakage to increase efficiency and promote the safety of your engine.

Since this model of the spark plug is made of iridium alloy, you can rest assured that it will make your engine more powerful and functional. This is due to the fact that the plug has an extremely high melting point designed to offer high durability. At least the pug can overcome cases of electric and heat wear. That is why this model is a perfect choice of spark plug for modern-day high-performance engines.

Furthermore, this product consists of a trivalent metal plating, which is a superior anti-corrosion and anti-seizing component to increase the longevity of your spark plug.

Best Value: NGK-7090 BKR5EGP-G Power Spark Plug

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NGK-7090 BKR5EGP-G Power Spark Plug is the real deal when it comes to the best spark plugs on the market. This is because it gives superior performance coupled with improved fuel efficiency, quicker starts, and lower emissions to keep the environment clean.

Just like other models, this one is equipped with a 0.6mm laser welded fine Platinum tip that reduces required voltage, ensuring high durability and a consistently stable spark. In addition to that, this model uses special configurations on the insulator noses. These configurations play a great role in improving throttle response or preventing fouling.

At the same time, the model uses its corrugated ribs located on the insulator control flashover for better performance. For precise gap maintenance, this spark plug combines the center electrode and a platinum alloy construction to produce greater sparks in the engine. Trivalent metal plating comes in handy to offer superior anti-seizing and anti-corrosion properties. The triple gasket seal on this model eliminates combustion gas leakage to enhance performance.

Best Pick: Denso PK20TT Platinum Spark-Plug

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If you are looking for the best spark plug to help your car engine work efficiently, look no further than Denso PK20TT Platinum Spark Plug. As the name suggests, this spark plug is made of durable and reliable platinum material to serve you longer.

This model features twin-tip technology that comprises both titanium and platinum electrodes for enhanced performance. The electrodes come in the form of 11 mm for the platinum center electrode and 11 mm for the titanium ground electrode

Additionally, this spark plug is designed to improve fuel economy. It can also provide better acceleration including faster starts compared to all other types of single platinum spark plugs.

As if that is not enough, Denso PK20TT Platinum Spark Plug has a purified aluminum powder insulator to offer exceptional dielectric strength. The same powder plays a significant role in thermal conductivity to allow the material to withstand extreme stress

Best Gap Firing Technology: Bosch 4417 Platinum Plus-4 FGR7DQP Spark Plug

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When it comes to the best gap firing technology, no other type of spark plug rivals Bosch 4417 Platinum Plus-4 FGR7DQP Spark Plug. This model features the four yttrium- enhanced ground electrodes to deliver the longest and most powerful spark for your car engine to start. This piece of revolutionary surface-air gap firing technology assures you the ultimate engine performance for quite a long time.

The four yttrium-enhanced ground electrodes come to offer optimum access to the mixture of air and fuel-air/fuel for efficient combustion. Also, the yttrium alloy ground electrodes help reduce gap wear as well as oxidation for extended engine performance life.

Aside from that, the electrode gap comes when it is already a factory set for easy and timeless installation. On top of that, the electrode gap does not require any adjustment to perform efficiently.

Best Affordable: ACDelco 41-993 Professional Iridium Spark Plug

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With ACDelco 41-993 Professional Iridium Spark Plug, you can be sure of everlasting engine performance for less money. The plug is made of top-quality iridium core material to offer better engine idle stability as well as smoother performance for your vehicle.

The same iridium material allows for smaller and more efficient electrode designs to improve the cold starting of the engine. Furthermore, this material enhances quicker acceleration to save you time and fuel consumption.

Iridium fine-wire electrodes on this spark plug help improve ignition while burning away carbon deposits at the tip. In general, the burning and discouraging formation of carbon deposits help to improve fuel economy for your car.

Apart from that, the piece of a seal suppressor blocks any radio frequencies that may affect your vehicle’s electronics when the engine is running. The suppressor seal also meters spark energy to prolong electrode life in addition to sealing against combustion leakage for maximum performance.

Best Price: NGK 6703 BPMR7A SOLID Standard Spark Plug

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Here is another product from NGK Standard Spark Plugs designed to make your outdoor equipment more efficient and practical. NGK 6703 BPMR7A SOLID Standard Spark Plug is a must-have if you own a motorcycle or chainsaw among other simple machines.

This model is treated with high-quality corrosion-resistant plating material for durability. Also, these materials ensure easy installation and removal of the spark plug from the engine.

Since this spark plug is made of 98% pure copper core materials, it can deliver increased heat dissipation. As a result, it is a more reliable plug for starts because it has a low risk of overheating while the engine is running.

Its cold-rolled threads are also important features that assure you of cross-threading prevention of damage to engine cylinder heads. The plug comprises trivalent plating that helps to eliminate your need for anti-seize.

Moreover, the corrugated ribs on each plug prevent flashovers to maintain the working conditions of your engine. These corrugated ribs are made from high-grade aluminum silicate ceramic to maintain the whole structure of the spark plug.

Best Durable Material: Autolite APP5325 4PK Double Platinum Spark Plug

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Although it is designed to offer vehicle-specific fit, Autolite APP5325 APK Double Platinum Spark Plug works efficiently on your car engine. It comprises full platinum tips to primarily ensure that there is no gap erosion for everlasting engine performance.

Better still, this model works great to optimize engine performance and improved fuel economy to save you some money in the process. The necked-down center electrode on this model fires faster and cleaner sparks to improve acceleration.

Despite that optimal performance, this model of spark plug uses less voltage to provide easier starts. Most importantly, it consists of a high-quality nickel alloy side electrode to maintain precise gaps for prolonged performance in various conditions.

Best Ignitability: Champion Iridium 9407 Spark Plug

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If you are in need of optimal performance look no further than Champion Iridium 9407 Spark Plug. This is a perfect type of spark plug that can give you value for your money. This is because it consists of a fine-wire iridium center electrode for enhanced performance and unmatched efficiency when it comes to producing powerful sparks to start your car engine. Plus,

there is the platinum ground included delivering maximum life and reliable acceleration.

The exclusive heat-active alloy material used in the construction of this model enables electrodes to achieve optimal temperature quickly. The same material remains stable under any type of engine load throughout.

No wonder this model works perfectly with any engine model, giving out better performance despite the available ignition system. Champion Iridium 9407 Spark Plug assures maximum power output for your car engine. This happens due to the plug’s ability to make a faster throttle response using a focused spark. The plug is compatible with different models of vehicles including Acura, Audi, Dodge, Jeep, Chrysler, Honda, Volkswagen Porsche, Ram, and Mitsubishi.

Best universal Fit: E3 Spark Plugs Power Sports Spark Plug

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E3 Spark Plugs Power Sports Spark Plug is built to provide you with a universal fit. This means you can use this model for almost all car engines, especially those in sports cars. That is why this type of spark plug is popularly known as the most ideal replacement racing spark plug. The plug is also a great choice of engine accessories used today by quite a number of professional car drivers in different parts of the world.

E3 Spark Plugs Power Sports Spark Plug is specifically designed with you in mind. The plug comprises colder heat ranges than most factory plugs to promote performance modifications while handling intense conditions as required.

Also, this model contains a Yttrium-enhanced alloy as part of its construction. The main reason for including the Yttrium-enriched alloy is to help the plug achieve up to an 8% reduction in all side wire temperature. As a result, the spark plug is able to improve durability including less pre-ignition for your vehicle’s engine.

Apparently, the E3 Spark Plugs Power Sports Spark Plug has a thread diameter of about 12mm, a thread reach 0.750 inches, and a hex size of up to 5/8 inches to provide a universal fit for a wide range of automobiles used today. Most importantly, this spark plug comes with a limited lifetime warranty to help you gain some confidence in its quality and functionality.

Best Customized Compatibility: Bosch Automotive 9603 Double Iridium OE Replacement Spark Plug

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No other type of spark plugs offers the best compatibility like Bosch Automotive 9603 Double Iridium OE Replacement Spark Plug. This is attributed to the fact that this model is engineered to deliver both high performance to your engine and unmatched durability. That is why it represents the most outstanding of OE spark plug cutting-edge technology.

What is more, the ultra-fine wire design for this model combines with a laser-welded tapered ground electrode to deliver optimum performance. At the same time, this spark plug uses its ground electrode and iridium center electrode to help it overcome the need for gapping.

With this model, you can easily and quickly unlock the performance and efficiency of your engine. This is made possible thanks to the extreme durability that the plug provides through its 360-degree continuous laser welding features that help to fuse the firing pin.

There is also exceptional durability coupled with performance from the ultra-fine design of this spark plug, The copper core material comes in to provide a broader range to get rid of pre-ignition and fouling. Additionally, the fine wire-firing pin helps to reduce voltage requirements while the copper core ground electrode is included in the design to provide better and improved heat transfer.

On the other hand, the nickel-plated shell combines with rolled threads to eliminate the need for anti-seize and protect against corrosion. The ribbed insulator is another feature that plays a crucial role in preventing flashovers to maintain the working condition of your engine.

Best Simple Design: NGK 4549 CR7HSA Standard Spark Plug

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NGK 4549 CR7HSA Standard Spark Plug is built to meet the needs of your automobile. Even though it comes in a single piece in a package, this spark plug model assures you of great performance to keep your engine running longer. This explains why NGK 4549 CR7HSA Standard Spark Plug comes with numerous features in addition to its superior materials.

The plug features corrosion-resistant plating to make it not only durable but also to ensure easy installation as well as removal. In simple terms, the plug is built to make your work easier. The core material on this spark plug features 98% pure copper to deliver increased heat dissipation for both durabilities and for more reliable starts. Also, this material ensures a lower risk of overheating the entire structure of the spark plug for optimal performance.

Its cold-rolled threads are included to prevent cross-threading that might cause some damage to your engine cylinder heads. Besides, the spark plug comprises a trivalent plating to eliminate the need for anti-seize. Other features include the corrugated ribs that prevent flashovers as well as the high-grade alumina-silicate ceramic to extend the longevity of your spark plug.

Best Spark Plugs Buying Guide

One thing you need to know is that all spark plugs are not the same in terms of design and features. Despite their differences, they are created to fit the model and make of your car engine. Not to mention delivering the peak performance throughout. Below are guidelines you need to follow when searching for the best spark plugs for your requirements.

Key Features to Consider Material

The first thing to look out for when buying spark plugs is the material. Make sure you choose the material that suits your requirements. In this regard, copper is suitable for older versions of vehicles. These old model vehicles have a low voltage distributor-based ignition, so they need plugs made of copper material.

Iridium and platinum are ideal for the last engine models without distributors. In this case, platinum will deliver a great mix of performance, longevity, and economy. On the other hand, iridium will deliver the highest results but at a considerably higher price. Most significantly, go for the spark plugs that are specified by your car or truck’s manufacturer.

Size

The size matters the most when it comes to choosing the best spark plugs. Here, the size refers to the thread or nut on each type of spark plug. Most countries prefer nut and thread sizes ranging from 10mm, 12mm, 14mm, 16mm all the way to 17.5mm, 18mm, or 20.63mm. Therefore, choose the most appropriate size of the thread or nut that you are sure will fit your engine.

Heat Range

Most spark plugs are specified as” hot” for a good reason. That is when they are better heat insulators. Alternatively, they are referred to as “cold” if they can lower the temperature of the plug’s tip by conducting heat out. Generally, the heat range of spark plugs is usually denoted with a number. Some brands use the ascending numbers to denote the hot plugs while others do vice versa for cold spark plugs.

Gap Style

Every spark plug is carefully engineered with a spark gap. This small gap can be adjusted with the help of a gapper tool designed only for spark plugs. In most cases, one plug can be designed to serve several engines. This type of spark plug can be adjusted to create different gaps depending on the type of engine they are going to work on.

Typically, spark plugs for car engines have gaps ranging from 0.6 to 1.8 millimeters. Always look for a gap gauge to help you determine the gap for a given model of the spark plug to be sure that it is within a specified range.

Types

Spark plugs are available in various types. These different types come as a result of the materials used in their construction. They include:

• Iridium spark plugs
• Double-iridium spark plugs
• Platinum spark plugs
• Double-platinum spark plugs
• Copper spark plugs

Top brands

Different models of spark plugs belong to different brands as well. These brands are as follows:

• ACDelco
• Bosch
• NGK

The Price

Just like other products, the best spark plugs have different price tags to meet different people’s needs.

Below is their price range that you need to know:

Under$3:Several spark plugs are available in this price range. As a buyer, you should do enough research before buying cheaper spark plugs in relation to their vastly varying quality. Between $3 and $9: A large percentage of spark plugs are within this pricing segment. Quite a number of spark plugs fall within this price range due to the fact that they offer a blend of longevity, value, performance, and efficiency. $10 and more: Most spark plugs in this category tend to be durable because of their premium materials, efficiency, longevity, unparalleled performance, and advanced electrode design.

Benefits

The best spark plugs come with many benefits. Some of these benefits include:

• Improve performance of the vehicle’s engine
• Increase fuel efficiency
• Lower down exhaust emission
• Enhance smoother engine idle
• Increase fuel economy
• Enhanced reliability
• Improve engine response and acceleration
• Lower the risk of damage to the engine or other components

Best Spark Plugs Frequently Asked Questions (FAQs)

Q: What’s a spark plug?
A: A spark plug is one of the most important components in a car. It is actually a small threaded metal device with conductive metal components. These components are separated by electrical insulators. Each spark plug assembly consists of a terminal located at one end while an electrode tip is strategically placed at the other end.

Between the two components, there are several threads that help the spark plug to get tightly installed into specially designed openings within the engine’s cylinder heads. When an electrical current comes into contact with the spark plug, it creates a brief electrical arc or rather ‘spark’. The spark forms in-between the two electrodes inside the engine cylinder. It is this spark that ignites the mixture of fuel and air inside the engine, causing an explosion that produces enough power to drive the engine.

Q: Can I modify my plug’s electrode gap?
A: It depends on the type of spark plug you are using. Some models come with a pre-set gap that makes the adjustment easy. A good example is the nickel spark plugs which have a gap that you can easily adjust.

To achieve this goal, you must always use special spark plug gapping tools to alter the gap. However, you should never modify the gap on iridium, platinum, or twin spark plugs to avoid damaging the delicate electrodes.

Q: What’s the working mechanism of a spark plug?
A: Each spark plug has an ignition coil or a spark plug wire mounted on one side of the plug. The electrode tip is the component that sits inside the cylinders or combustion chambers of an engine. Each spark plug is rigidly mounted in place while a tiny gasket forms a tight seal that prevents the pressure created during the combustion process from escaping.

On the other hand, the ignition system of your vehicle sends a controlled electrical current to the spark plug under extremely precise timing. The moment a current flows through the plug, it creates a spark at the electrode tip inside the engine to aid the combustion process.

Q: Do I need special tools to replace a spark plug?
A: Absolutely! Just confirm with the owner’s manual to find the correct tool to remove the worn-out plug and to install a new one. If you are cleaning or inspecting an existing plug, you are advised to clean the spark plug’s threads using a wire brush. This is to prevent any damage to the plug’s threads while inside the engine’s head.

Q: How often should I replace my spark plugs?
A: In most modern vehicles, spark plugs need to be replaced infrequently. In this case, you can change them every 80,000 or 100,000 miles. This interval may be a little shorter with specialty vehicles or certain applications.

The custom-built performance engines or higher-performing cars may need new spark plugs more often. For instance, racing cars may need their spark plugs changed almost daily. But in normal vehicles, you can replace the old spark plugs after a few years. Otherwise, you may need to consult with the owner’s manual to find out how often you need to change your vehicle’s spark plugs.

Q: Which type of spark plug should I settle for?
A: There are many types of spark plugs sold today. Most of these engine accessories are available in many sizes, shapes, and variations despite looking similar and performing the same function. But your selection of the best spark plug should be based on the physical dimension of each model. The dimensions will ensure a tight fit and optimal functionality on your vehicle’s engine.

Most spark plugs are designed for specific functions depending on their precise physical characteristics or heat ranges. As such, most spark plugs come fully loaded with unique features in relation to the design and structure of their electrodes. Not to mention the materials used to make them among other factors.

As a matter of fact, there are many different variations of spark plugs. Most of them are based solely on the physical characters of their electrodes. So, which type is appropriate for you? If your vehicle has a non-modified engine, you may choose the precise spark model, made and highlighted in your vehicle’s manual.

Quite a number of these spark plugs were carefully selected by experts as the right choice for your engine’s durability, performance, and efficiency. In most cases, they are listed in a specific order based on numbers and codes that will help you find a perfect match for them.

Q: How do I find the best spark plug for my vehicle?
A: You can visit an automotive store near you or turn to online automotive parts catalogs to be your primary reference. The catalog will give you details about the model, make and engine.

Q: Does it help much to clean my spark plugs?
A: It depends on the situation at hand. In most cases, you may not need to clean your spark plugs. But during routine maintenance of your lawn and garden equipment, you may inspect and subsequently clean the spark plugs’ tips. Other installations such as Powersports need the cleaning of spark plugs depending upon the frequency of use and application.

Q: What performance increase should I look forward to after upgrading my spark plugs?
A: The main idea of upgrading spark plugs is to improve the performance of your vehicle’s engine. A new plug can enhance power performance to about 5% although this depends solely on the engine. The modern-day engines come with high-performance spark plugs, making the difference a little bit negligible. As a result, the main improvement in engine performance leads to a better starting as well as a smoother operation.

Q: Is it right to apply some grease on my spark plug threads?
A: Not at all. Experts discourage the use of any form of lubricant-including grease-to is applied on the spark plugs. This is because grease can damage the plug or cause it to loosen when the engine vibrates. Only in some special cases, you can apply grease. A small amount is recommended especially for those spark plugs used in LPG-powered forklifts.

The Verdict

When buying the best spark plugs make sure you choose the correct number that matches your engine. Quite a number of engines come with one spark plug for each cylinder but only a few have two per cylinder. This means that you need to check your engine to be sure of how many plugs you can buy. Also, ensure that you use the same model of spark plugs throughout your engine.

Make the habit of changing all plugs at once to make the engine run efficiently. While choosing the right plugs for your engine you must consider essential factors that make these car accessories functional as highlighted in the review above. On that note, our best overall spark plug is NGK-6619 LFR6IX-11 Iridium Spark Plug. This model comes with all features that every spark plug should have. Besides, it is durable and affordable. However, other models are equally important and will make your engine perform optimally.