The best iridium spark plug brands are widely considered to be NGK and Denso, often preferred by mechanics for their reliability, durability, and performance, with NGK frequently cited as the top choice, especially their Iridium IX series, while Denso's Iridium Power plugs are also highly rated for strong performance and efficiency. Other reputable brands include Bosch, known for setting industry standards, and OEM suppliers like ACDelco.
Denso plugs are installed on almost every automobile model manufactured in Japan. The iridium used in them has a superior hardness. The electrode's diameter in these plugs shrinks more than an NGK. For this reason, Denso plugs won't last longer than NGK .
Best overall reliability and availability: NGK or Denso. Best for Japanese cars: Denso (or NGK when OEM specified). Best for European cars and diesels: Bosch. Best long-life/performance: Iridium plugs from NGK, Denso, or Bosch. Best budget replacement: Autolite or Champion (match specs carefully).
NGK builds two types of iridium spark plugs: OE Iridium and Iridium IX®. Every plug in the Laser Series was designed for an OEM application. All dual precious metal plugs are designed to provide maximum longevity.
Without a doubt—especially if you're looking for a cost-effective, low-maintenance upgrade. While NGK Iridium spark plugs may cost more initially, their longer lifespan, reduced maintenance, and enhanced performance make them a smart investment in the long run.
NGK Iridium IX spark plugs offer superior ignition performance, better fuel efficiency, and longer lifespan compared to standard plugs, ensuring a smoother and more responsive ride.
NGK and Bosch are both top-tier spark plug brands, but NGK often gets the nod for Japanese/Asian cars and quicker ignition, while Bosch is a go-to for European vehicles, known for durability, especially with their advanced designs like multi-ground electrodes. Many users find NGK offers better low-end responsiveness, while Bosch provides excellent durability and performance, with personal preference and vehicle compatibility being key factors, as both perform well but use different design philosophies.
The main disadvantages of iridium spark plugs are their significantly higher cost and increased fragility, requiring careful handling during installation, as the fine iridium tip can be easily damaged, negating benefits and potentially causing engine issues; they also can't be cleaned if fouled, meaning a fouled plug must be replaced, unlike some copper plugs.
Although the NGK factory will set the gap to a preselected setting, this may not be the right gap for your particular engine. The incorrect plug gap for your engine can contribute to a high rate of misfires, loss of power, plug fouling, poor fuel economy and accelerated plug wear.
Copper spark plugs run cooler and provide more power in performance driving situations. They are often installed as original equipment in turbocharged engines and engines with higher compression ratios. Copper spark plugs are also often used in older (pre-1980s) vehicles with a distributor-based ignition system.
What does 'NGK' stand for? 'NGK' stands for 'Nippon Gaishi Kkabushiki-gaisha' which is the Japanese name of NGK Insulator Company Ltd., the company which NGK SPARK PLUG was spun-off from in 1936.
In most engines the number one spark plug is in the number one cylinder which is the forward most cylinder at the front of the engine.
NGK SPARK PLUG CO ( (JP:5334) ) has shared an announcement. Niterra Co., Ltd. has announced its acquisition of DENSO Corporation's Spark Plug and Exhaust Gas Sensor businesses.
NGK and Denso are two leading Japanese brands that have proven their reliability and technological excellence over decades. Selecting the right spark plugs for your specific car model is an important step towards stable and economical engine performance.
When comparing NGK vs Denso, both brands stand out for their quality and performance. However, nuanced differences might make one a better choice over the other for your specific needs. Similarities: Both brands provide spark plugs made from premium materials such as iridium and platinum.
Overheating: Overheating can cause the spark plug's electrodes to wear out more quickly. This is often due to issues like incorrect spark plug gap, poor fuel quality, too little fuel available for combustion, or engine overheating.
Japan remains NGK SPARK PLUG's manufacturing heartland, home to its headquarters and four of its largest production plants.
As well, your car might not run properly if it's intended to use iridium spark plugs and they've been downgraded. Why are platinum spark plugs better? Platinum has a higher melting point and is denser than copper, making it an excellent choice for long-lasting replacements.
Iridium spark plugs have a fine wire center electrode that requires less voltage to create a spark. This results in a more efficient combustion process, better fuel economy, and a smoother idle.
The estimated mileage of iridium spark plugs – depending on the thickness of the central electrode and the construction of the ground electrode – ranges from 60,000 km up to 120,000 km in the case of DENSO Super Ignition Spark Plugs, which feature a protruding ground electrode, like DENSO's Twin Tip (TT) Spark Plugs.
Platinum spark plugs offer better longevity and heat tolerance. NGK and Bosch both produce high-quality platinum spark plugs that offer a good balance between performance and price. If you're looking for the exceptional life and performance, iridium is the way to go.
Denso Iridium spark plugs use a much thinner electrode than even the NGK. Given how long the NGK electrodes last you could argue the NGK are over engineered and reducing their diameter would have no effect on their service life.
Bosch Iridium Spark Plugs are engineered to deliver both high performance and long life, representing advanced OE spark plug technology. The ultra-fine wire iridium center electrode pin delivers best performance. Unlock the performance in your engine with Bosch Iridium Spark Plugs.