Copper spark plugs are among the cheapest and most widely used spark plugs available.
But that doesn’t necessarily make them the best choice for every engine.
While copper plugs offer strong conductivity and cooler operating temperatures, they also wear out much faster than iridium or platinum spark plugs.
In this guide, we’ll explain how copper spark plugs work, their pros and cons, when they’re used, and whether they’re a good fit for your vehicle.
This Article Contains:
- What Are Copper Spark Plugs?
- What Are the Benefits of Copper Spark Plugs?
- What Are Copper Spark Plugs Used For?
- 4 FAQs About Copper Spark Plugs
Let’s begin!
What Are Copper Spark Plugs?
Copper spark plugs (also known as conventional plugs or copper-core spark plugs) are a type of spark plug that has a copper core and a nickel alloy outer material. Like all spark plugs, their primary functioning elements are the ground electrode (side electrode) and central electrode, responsible for creating the electric spark that combusts the air-fuel mixture.
Copper spark plugs have a number of advantages. For one thing, they’re far less costly and run a lot cooler than high-end plugs.
But how do they compare to iridium or platinum spark plugs?
Moreover, what are the benefits of using copper spark plugs in your ignition system?
Let’s find out.
What Are the Benefits of Copper Spark Plugs?
Unlike most other spark plugs, copper spark plugs generally do not last more than 20,000 miles. The nickel alloy on their electrodes wears faster than precious metal plugs.
So why do people still use them?
Low cost is a factor. Conventional plugs are a lot cheaper than expensive iridium or platinum spark plugs. A single regular spark plug can start from as low as $2 per piece, whereas iridium or platinum plugs can range from $20-$100.
Moreover, copper spark plugs do not overheat and can be used in a wide variety of heat ranges. This makes them a good option for a lot of vehicles.
Now that we know why people use copper spark plugs, let’s understand what they’re used for.
What Are Copper Spark Plugs Used For?
Since longevity is not really a strong suit for copper spark plugs, they’re typically not recommended for newer car models. However, they are an ideal fit for racing cars and other modified engines.
This is for a couple of reasons:
- Most racers tend to change their spark plugs very often, so the shorter lifespan of the regular spark plug doesn’t really matter for racing cars.
- Conventional plugs are very cheap. So changing them very often is economical instead of going for other spark plugs.
Not to mention, as copper spark plugs perform brilliantly in a wide selection of heat ranges, they offer maximum power without costing too much. And as they run cooler, they’re often well-suited for performance driving situations.
However, copper spark plugs usually require more frequent maintenance because their nickel-alloy electrodes wear down faster than iridium or platinum plugs. That’s why they’re better suited for vehicles where regular tune-ups are expected.
Moreover, older vehicles that tend to operate at higher temperatures require copper plugs since they rarely overheat. Apart from racing cars and older vehicles, copper spark plugs are also used in late-model vehicles with turbocharged engines (with higher compression rates).
Next, let’s dive into some details about copper spark plugs.
4 FAQs About Copper Spark Plugs
Let’s look at some common queries about copper spark plugs and their answers.
1. How Do Spark Plugs Work?
A spark plug is like a small electrical device that creates the electrical energy necessary to ignite the air-fuel mixture in the car’s combustion chamber. In short, they play an important role in your car’s ignition system.
So how do they do that?
A spark plug is mounted onto the cylinder head with the center electrode and ground electrode facing into the cylinder.
When the ignition coil induces a high voltage, that voltage travels through the spark plug’s central electrode, jumps the spark gap, and creates a spark that ignites the air-fuel mixture. This leads to a tiny explosion in the cylinder and helps keep the pistons moving, so the engine turns on.
A strong spark means better combustion, reduced build-up of combustion debris, and improved emissions.
2. How Long Does a Copper Plug Last?
The copper spark plug can last for up to 20,000 miles, after which it will need to be changed.
While some brands do claim that copper spark plugs can last up to 50,000 miles, it’s best not to push them. It’s important to follow your car’s recommended spark plug change interval (as mentioned in the service manual).
At the same time, you should also regularly inspect any broken spark plug wire or faulty plug. Failure to do so could negatively affect the car’s performance and cause misfires and carbon fouling.
3. Are Copper Spark Plugs Better Than an Iridium Plug?
It depends. Copper spark plugs conduct heat better and do not overheat nearly as much as iridium plugs. On the other hand, they do wear out faster and need to be changed very often.
In contrast, precious metal spark plugs like single platinum, double platinum spark plugs, or iridium spark plugs are more durable and can last up to 100,000 miles. However, they do tend to be very expensive. Another major difference is the replacement interval. Many iridium spark plugs can last over 100,000 miles, while copper spark plugs may need replacement several times within that same period.
So in reality, the best spark plug for your car is the one recommended in your owner’s manual. When in doubt, an OEM plug is a safe bet.
NOTE: It’s also important that you never downgrade to copper spark plugs if your car recommends iridium or platinum plugs. Despite the lower costs of copper plugs, you may end up damaging your engine, leading to costly repairs.
4. Can I Use a Copper Spark Plug Instead of a Platinum Plug?
Not really. In general, you want to stick to the recommended spark plugs in your owner’s manual.
Platinum spark plugs are very similar to copper spark plugs, except they have a platinum disc at the central electrode. But keep in mind that different types of spark plugs may operate at a different heat range.
Modern engines usually require precious metal plugs, like a platinum spark plug or iridium spark plug, because they run at a lower temperature and simply cannot use copper plugs.
So, unless your mechanic recommends it, don’t upgrade or downgrade your car’s spark plugs on your own. You want to ensure the best spark plug for your engine.
Choosing the Right Spark Plug for Your Vehicle
Spark plugs play a crucial role in the combustion chamber. As a result, a faulty or worn spark plug can greatly affect the engine’s performance and fuel economy. Copper spark plugs, in particular, tend to wear out faster than others. So you need to keep a close eye on their mileage and get them changed routinely.
Who better than AutoNation Mobile Service to handle your spark plug replacement?
AutoNation Mobile Service is a mobile auto repair and maintenance company that offers convenient online booking and several car care services. Fill out this form to get an accurate quote for spark plug replacement.
And don’t forget to contact us in case of any automotive-related queries, repairs, or maintenance needs!