Spark plugs are a critical component of engine maintenance, yet many drivers remain unaware of this requirement. Old, worn, or dirty spark plugs will decrease your engine's ability to perform, as they will be unable to ignite the fuel/air mixture as efficiently as they should. Having good spark plugs will make your engine run smoother, cleaner, and consume less fuel. The best spark plugs make use of the latest technology and materials, and can achieve both high performance and durability without compromise.
Why it's best: As the name suggests, the Bosch Platinum IR Fusion mixes two different materials together to increase performance. The center electrode contains a platinum/iridium blend, while the ground electrodes feature yttrium enhancements for better performance. These spark plugs are more expensive than standard platinum plugs. Read Full Review
Why it's best: One of the main benefits of using iridium in spark plugs is its extremely high melting point - nearly 2500ºC. The Denso Iridium Power spark plug takes full advantage of this fact by using a fine-tipped 0.4 mm diameter electrode in place of the more traditional wide-diameter offerings. A standard electrode of that diameter would more than likely melt after prolonged use, but the Iridium allows for a more precise, controlled spark-to-ignition process. Combined with Denso's exclusive U-Groove pattern ground electrode, this allows the Iridium Power to handily outperform its competitors. However, this performance comes with a premium price tag - at more than three times the price of a standard spark plug, it's hard to make a case for the average, casual driver. If you are a performance enthusiast or a long-distance commuter, the cleaner burning capability and potential for increased fuel economy with the Denso Iridium Power may be worth looking into. Read Full Review
Why it's best: You'll find NGK spark plugs under the hood of many cars as they leave the factory, which shows just how well these spark plugs perform. The Iridium IX spark plug are practically maintenance-free, and reliably ignite fuel/air mixtures within the engine. Unfortunately, these spark plugs are pricier than the alternatives. Read Full Review
Why it's best: Aside from being an excellent overall spark plug, AC Delco Iridium spark plugs are used as original equipment in premium and high-performance products from GM. Thanks to the higher melting point that the iridium electrode offers, this allows a more powerful spark that would wear out standard spark plugs. The more powerful spark ensures a more thorough ignition of the fuel/air mixture, which means your engine will run cleaner and more smoothly. The AC Delco Iridium spark plug requires little to no maintenance, though it is always a good idea to check gap spacing every once in a while if you suspect that the spark plugs are becoming worn. These spark plugs are rated to last 100,000 miles, and will offer substantial performance for the entire duration of their useful service life. Read Full Review
Why it's best: For the vast majority of drivers on the road today, the Bosch Platinum +4 can be considered the best all-around spark plug. The Platinum +4 achieves its high performance by featuring clever tricks such as employing four (as opposed to one) yttrium-enhanced ground electrodes. This creates a powerful, long-duration spark which is better suited to igniting the fuel/air mixture in any engine, high performance or not. This spark plug requires no gapping or maintenance - you can simply install these in the engine and 'forget' about them until the next time you need a tune-up. The price of the Bosch Platinum +4 falls neatly in between a traditional spark plug and Bosch's own Platinum IR Fusion model, meaning that these performance spark plugs can even be considered relatively affordable. Read Full Review