What Are The Differences Between Iridium And Platinum Spark Plugs?

For users looking for premium, high performance spark plugs for their gas ignition equipment, the choice comes down to iridium and platinum spark plugs. These provide a far greater level of reliability, efficiency, and performance, and a longer service life than the more common copper spark plugs, but do so at a higher price.

At a structural level, the only difference between iridium and platinum spark plugs is the metal used for the central electrode. So, what is the practical difference between an iridium and platinum spark plug, and is it worth spending the extra money for iridium? This is the question we will explore in this article.

Price and Value

Of the two, iridium spark plugs are more expensive than platinum – considerably more so at the moment due to the current global scarcity of iridium brought about by the pandemic. So, rarity is one factor making iridium the costlier of the two options, but also because iridium spark plugs are superior to platinum spark plugs in terms of strength, durability, efficiency, and performance. For many businesses, this makes it worth spending the extra to secure iridium spark plugs, as they provide superior value to their platinum alternatives.

Strength and Durability

Iridium is a far stronger metal than platinum, capable of taking up to eight times as much wear and tear as a platinum spark plug before losing efficiency. This means that iridium spark plugs are less likely to fail than platinum spark plugs, need replacing less often, and perform better under tough conditions.

Iridium is also a superior metal for high temperature applications, with a higher melting point than platinum. In ignition chambers expected to reach temperatures over 1,760°C (the melting point of platinum), iridium spark plugs are the only practical choice.

Efficiency and Performance

In terms of day-to-day performance, platinum and iridium spark plugs are similar, so it’s perfectly acceptable to interchange spark plugs of the two metals, or to ‘downgrade’ to platinum spark plugs as a cost saving measure. Both platinum and iridium spark plugs are superior to copper spark plugs on every criteria. However, iridium spark plugs are less prone to erosion than platinum plugs, so they last longer, and are less likely to leave waste metal deposits in the combustion chamber.

Next Steps

At RM Walsh, we stock a wide range of iridium and platinum spark plugs as part of our catalogue of gas ignition equipment for industrial engines. To find out more, or to request a quote, please get in touch with one of our technical sales team today.