NGK Iridium IX Spark Plug Box of 4 (YR5IX)

These NGK Iridium IX spark plugs are a solid option for anyone looking to get the most out of their engine, especially if you've got a modified or high-performance setup. They're designed to give you a more consistent spark, which can lead to better acceleration, improved fuel economy, and a smoother idle. This set comes with four plugs, perfect for most 4-cylinder engines or as an upgrade for vehicles that use four plugs per engine.

The fine iridium center electrode is notably durable, lasting much longer than standard platinum plugs. This means you can go longer between changes, and you'll maintain that strong spark for a longer period. The iridium alloy also has a very high melting point, making it well-suited for today's hotter-running engines. Plus, the trivalent metal plating on the plug body helps prevent corrosion and makes them easier to remove down the road.

If you're looking to get a bit more out of your classic Chevrolet, Buick, or GMC, these plugs are a great choice. They fit a wide range of vehicles from the 70s and 80s, offering a noticeable improvement over older, standard plugs.