The job of a spark plug is to provide high voltage electrical spark needed to ignite the fuel air mixture in the combustion chamber. This creates the combustion that powers your car.
Spark plugs are classified according to the metal the centre and side electrodes are made of. The three main types are copper, platinum and iridium. Silver ones also exist but are rare.
Read: How To Read Your Spark Plugs And Tell Good From Bad
Here is a look at them in detail:
Copper Spark plugs
The centre electrode is made of copper core coated with nickel alloy. The nickel alloy wears fast from the high pressure and temperatures in the combustion chamber. As a result, they have a short lifespan and foul easily. Copper spark plug is the oldest and has the widest diameter of the three. It is also the cheapest and most common.
Advantages
- Cheapest of the three
- Ideal for older cars and performance cars with turbo charged engines
Disadvantages
- Shortest lifespan, need to be replaced after 20,000 miles
- Needs more voltage to generate a spark
Platinum Spark Plugs
The changing ignition systems called for a spark plug that could withstand higher energy in the combustion chamber. This came in form of platinum spark plugs. A platinum spark plug is a copper spark plug with a platinum disk on the tip of the centre electrode.
Platinum is able to withstand more heat and pressure than nickel alloy and lasts longer, up to 100,000 miles. This makes platinum spark plugs longer lasting than copper ones. The high heat also meant deposits can be burned off preventing fouling.
Platinum spark plugs come in two flavours: single and double platinum. While a single platinum spark plug has the platinum disk welded on the top of the centre electrode, a double platinum spark plug has platinum disk on both the centre and side electrodes. Double platinum spark plugs are ideal for wasted ignition systems which causes wear to both the centre and side electrodes.
Advantages
- Lasts longer than copper spark plug
- Prevents carbon buildup
Disadvantages
- More expensive than copper spark plug
Iridium Spark Plugs
Multiple times better and harder than platinum, iridium spark plug has superior qualities of the three. It lasts longer and is more efficient thanks to its thin centre electrode. Like platinum, iridium spark plug also exists in two variants: single and double. And like double platinum, double iridium has iridium on both the centre and side electrodes.
Advantages
- Lasts the longest
- Needs less voltage
- Is the most efficient in creating combustion
- Prevents carbon buildup
Disadvantages
- It is the most expensive
To know the recommended type of spark plug for your car, consult your owner’s manual. If the recommendation is for iridium spark plugs, do not downgrade to copper or platinum. It will affect your engine’s performance and you run the risk of damaging the engine altogether.
